Transplanter

Abstract

To provide a transplanter which can suppress a large force from suddenly acting on a power transmission mechanism of a seedling planting device when stopping the rotation of a planting rotary body, and can prevent damage or the like to components of the power transmission mechanism in a configuration in which the planting rotary body is rotationally driven by an electric motor.SOLUTION: A control unit performs, as stop control for stopping the rotation of a planting rotary body, performs control of varying a deceleration rate of a rotational speed of an electric motor according to a magnitude of an actual difference Δθ of a rotary phase being a difference between a phase detected by a phase detection unit and a predetermined target phase set as a stop position of the planting rotary body with respect to the phase.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a transplanter having a configuration in which a planting rotor is rotated by an electric motor. [Background technology]

[0002] In a conventional rice transplanter that continuously plants seedlings in a field using a planting device, a plate-shaped seedling mat placed on a seedling carrier that slopes downward at the rear is fed horizontally and vertically, and the planting claws of the planting device continuously scrape off the seedling mat one portion at a time to plant the seedlings. This type of rice transplanter is equipped with a rotary-type planting device as the planting device, which has a planting transmission case, a rotary case that is a planting rotor provided on both the left and right sides of the planting transmission case, and a planting claw device that includes planting claws supported by the rotary case.

[0003] Among such rice transplanters, there is one in which the rotary case is rotated using the driving force of an electric motor (see, for example, Patent Document 1). Patent Document 1 discloses a configuration in which a pair of left and right rotary cases are rotated by one electric motor, and a configuration in which one electric motor is provided for each rotary case. Patent Document 1 also describes, with regard to rotary case operation control, a control in which the rotary case is stopped at a phase where the planting tines are away from the field surface (the so-called upper stop position) by driving control of the electric motor. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5335446 Summary of the Invention [Problem to be solved by the invention]

[0005] In the above-described configuration in which the rotary case is driven to rotate by an electric motor, when the rotating rotary case is to be stopped at a predetermined phase (position), such as the upper stop position, the electric motor is stopped by, for example, cutting off power to the electric motor. Stopping the electric motor causes the rotation of the rotary case to suddenly stop, which causes a sudden large force to act on the power transmission mechanism downstream of the electric motor in the power transmission path. This can cause damage or deterioration to the transmission components, such as gears and shafts, that make up the power transmission mechanism.

[0006] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a transplanter that, in a configuration in which the planting rotor is driven to rotate by an electric motor, can prevent a sudden large force from acting on the power transmission mechanism of the seedling planting device when the rotation of the planting rotor is stopped, thereby preventing damage to the components of the power transmission mechanism. [Means for solving the problem]

[0007] The transplanter of the present invention comprises a running body, a planting unit supported on the running body and having a planting rotor that supports planting claws and is rotatably arranged, an electric motor for driving the planting rotor to rotate, a phase detection unit that detects the phase of the rotation of the planting rotor, and a control unit that controls the electric motor based on the phase detected by the phase detection unit, and the control unit performs stop control to stop the rotation of the planting rotor by controlling the deceleration rate of the rotational speed of the electric motor to vary depending on the magnitude of the difference between the phase detected by the phase detection unit and a predetermined target phase for the phase that is set as the stop position of the planting rotor.

[0008] In the transplanter of the present invention, the control unit performs control in the stop control to decelerate the rotational speed at a first deceleration rate, and then at a second deceleration rate lower than the first deceleration rate.

[0009] In the transplanter of the present invention, the control unit controls the rotation speed to be maintained at the rotation speed at the start point of the stop control from the start point to the point at which the rotation speed starts to be decelerated.

[0010] The transplanter of the present invention comprises a traveling body, a planting unit supported on the traveling body and having a planting rotor that supports planting claws and is rotatably arranged, an electric motor for rotating the planting rotor, a phase detection unit that detects the phase of the rotation of the planting rotor, and a control unit that controls the electric motor based on the phase detected by the phase detection unit.As a stop control for stopping the rotation of the planting rotor, the control unit controls to decelerate the rotational speed of the electric motor depending on the magnitude of the difference between the phase detected by the phase detection unit and a predetermined target phase for the phase that is set as the stop position of the planting rotor.If the rotational speed is below a predetermined threshold at the start of the stop control, the control unit increases the rotational speed to the threshold, maintains the rotational speed at the threshold until the magnitude of the difference reaches a predetermined value, and then controls to decelerate the rotational speed. [Effects of the Invention]

[0011] According to the present invention, in a configuration in which the planting rotor is driven to rotate by an electric motor, when the rotation of the planting rotor is stopped, it is possible to prevent a sudden large force from acting on the power transmission mechanism of the seedling planting device, thereby preventing damage to the components of the power transmission mechanism. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a left side view of a rice transplanter according to an embodiment of the present invention. [Figure 2] FIG. 1 is a plan view of a rice transplanter according to an embodiment of the present invention. [Figure 3] FIG. 1 is a plan view showing a power transmission configuration provided in a rice transplanter according to one embodiment of the present invention. [Figure 4]FIG. 1 is a block diagram showing the power and power transmission configuration of a rice transplanter according to one embodiment of the present invention. [Figure 5] FIG. 2 is a block diagram showing a control configuration of the rice transplanter according to one embodiment of the present invention. [Figure 6] FIG. 1 is a left side view showing the configuration of a seedling planting device and its surroundings according to an embodiment of the present invention. [Figure 7] FIG. 10 is an explanatory diagram of planting unit stop control according to one embodiment of the present invention. [Figure 8] FIG. 10 is an explanatory diagram of another example 1 of planting unit stop control according to one embodiment of the present invention. [Figure 9] FIG. 10 is an explanatory diagram of another example 2 of the planting unit stop control according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] The present invention aims to prevent damage to the power transmission mechanism of a seedling planting device by devising a control mode for the electric motor when stopping the rotation of the planting rotor, thereby suppressing the application of large forces such as recoil caused by a sudden stop to the power transmission mechanism. The following describes an embodiment of the present invention.

[0014] The configuration of a rice transplanter 1 as a transplanter according to this embodiment will be described with reference to Figures 1 to 6. In the following description, the left side (left side in Figure 2) and the right side (right side in Figure 2) when facing the front of the rice transplanter 1 will be referred to as the left side and right side of the rice transplanter 1, respectively.

[0015] As shown in Figures 1 and 2, the rice transplanter 1 of this embodiment is a riding rice transplanter that performs planting work while traveling with an operator inside, and is used to plant seedlings sequentially in a field.

[0016] The rice transplanter 1 comprises a traveling body 2 that constitutes a self-propelled traveling section, and a planting device 3 that serves as a planting section that is provided behind the traveling body 2. The planting device 3 is connected to the rear of the traveling body 2 so that it can be raised and lowered via a lifting link mechanism 4 that includes multiple links. While traveling on the traveling body 2, the rice transplanter 1 plants seedlings in a paddy field 6 that serves as a farm scene in a field 5 using the planting device 3.

[0017] The traveling machine body 2 has a machine body frame 7, left and right front wheels 8, and left and right rear wheels 9. The machine body frame 7 is configured in a framework shape using multiple frame members, and has a front frame section 11 that forms a horizontal frame portion, and a rear frame section 12 that forms a stepped section that is one step higher behind the front frame section 11. The left and right front wheels 8 are provided below the front frame section 11, and the left and right rear wheels 9 are provided below and behind the rear frame section 12. The machine body frame 7 is supported on the field by the left and right front wheels 8 and the left and right rear wheels 9. For convenience, the rear wheels 9 are shown in FIG. 1 by virtual lines (chain double-dashed lines).

[0018] A horizontal floor 13 made of a vehicle body cover or the like is provided above the front frame 11 of the traveling body 2. A driver's unit 10 for driving and operating the traveling body 2 and the planting device 3 is provided on the floor 13. A driver's seat 15 is provided in the center of the left and right rear of the driver's unit 10. A fuel tank (not shown) is provided below the seat 15.

[0019] An operating unit 16 is provided in front of the driver's unit 10 and is operated by an operator seated in a seat 15. The operating unit 16 is provided with a dashboard 18 on which a steering wheel 17 and the like are arranged, various operating pedals such as a speed change pedal and a brake pedal, and various operating levers such as a speed change lever, a planting clutch lever, and a lift operation lever.

[0020] An engine 20 serving as a drive source is provided in the center of the left and right sides of the front of the machine frame 7. The engine 20 is covered by a hood 21. The engine 20 is mounted on the front of the front frame portion 11 via vibration-isolating rubber or the like. The engine 20 is, for example, a diesel engine. Note that a motor or the like may also be mounted as a drive source for the rice transplanter 1.

[0021] A transmission 22, which has a power transmission mechanism including gears, brakes, etc. built into a transmission case, is provided behind the engine 20 on the underside of the traveling body 2. The power of the engine 20 is transmitted to the transmission 22 and used to drive the front wheels 8 and rear wheels 9.

[0022] Front axle cases 25 are attached to both the left and right sides of the transmission 22. A front axle 26 is rotatably supported by the front axle case 25, and front wheels 8 are attached to the front axle 26. A power transmission mechanism provided within the front axle case 25 transmits the rotational power of the transmission 22 to the front axle 26, thereby driving the front wheels 8 to rotate.

[0023] A rear axle case 28 is provided behind the transmission 22. The rear axle case 28 is connected to the transmission 22 via a connecting frame 29 that extends in the front-to-rear direction. The rear axle case 28 receives power from the transmission 22 via a transmission shaft 31 that extends from the rear of the transmission 22 and is arranged parallel to the connecting frame 29.

[0024] The rear axle case 28 has protruding case sections 28a on both the left and right sides that protrude rearward relative to the case main body. A rear axle 32 is rotatably supported by the left and right case sections 28a, and a rear wheel 9 is attached to the rear axle 32. A power transmission mechanism provided within the rear axle case 28 transmits the rotational power of the transmission 22 to the rear axle 32, thereby driving the rear wheel 9 to rotate.

[0025] In the traveling body 2, multiple stages (three stages in the example shown in FIG. 1) of spare seedling trays 33 are provided at positions on the left and right outer sides of the hood 21. Supplementary seedling mats are placed on the spare seedling trays 33.

[0026] As shown in Figures 3 and 4, the rice transplanter 1 is configured as a hybrid rice transplanter, and includes, in addition to the engine 20, a motor generator 41 as a first rotating electric machine, an electric motor 42 as a second rotating electric machine, and a battery 43. In Figure 4, thick solid lines connecting elements indicate power lines, and thick dashed lines connecting elements indicate signal lines. Also, the outline arrows indicate the direction of power transmission.

[0027] The motor generator 41 is connected to the engine 20 via a power transmission unit so that power can be transmitted thereto. This power transmission unit is configured to directly or indirectly connect the rotating shaft of the motor generator 41 to the output shaft of the engine 20. A transmission, a clutch for switching between on and off of power, and the like are appropriately interposed between the motor generator 41 and the engine 20.

[0028] The motor generator 41 has both a function as a motor that provides power to the output of the engine 20 to assist the output of the engine 20, and a function as a generator that generates electricity by rotating with the output of the engine 20. The motor generator 41 functions as a three-phase AC motor when three-phase AC power is input, and rotates when power is input and functions as a three-phase AC generator. The motor generator 41 is controlled by a control device 50 (see FIG. 5) provided in the rice transplanter 1 via a first inverter 46.

[0029] The electric motor 42 supplies driving force to the planting device 3. In other words, the electric motor 42 is a power source provided separately from the engine 20 as a configuration for supplying power to drive the planting device 3. The electric motor 42 is a three-phase AC motor driven by three-phase AC power. The electric motor 42 is controlled by a control device 50 provided in the rice transplanter 1 via a second inverter 47. The configuration of the electric motor 42 (type of motor) is not particularly limited.

[0030] The battery 43 is supported at a predetermined location on the vehicle frame 7. The battery 43 is formed of a secondary battery such as a lead-acid battery or a lithium-ion battery. The battery 43 is formed, for example, by unitizing a plurality of battery modules each made of a secondary battery. The battery 43 is electrically connected to the motor generator 41 and the electric motor 42.

[0031] The battery 43 is electrically connected to the motor generator 41 via the first inverter 46 and supplies power to the motor generator 41 via the first inverter 46. The motor generator 41 can supply power to the battery 43 via the first inverter 46. In other words, the motor generator 41 can charge the battery 43. The first inverter 46 converts DC power output from the battery 43 into AC power and supplies it to the motor generator 41. The first inverter 46 also converts AC power output from the motor generator 41 into DC power and supplies it to the battery 43.

[0032] Furthermore, the battery 43 is electrically connected to the electric motor 42 via the second inverter 47, and supplies power to the electric motor 42 via the second inverter 47. The second inverter 47 converts DC power output from the battery 43 into AC power and supplies it to the electric motor 42. Note that, although the present embodiment employs a configuration in which an inverter is provided for each of the motor generator 41 and the electric motor 42, a configuration in which one inverter is shared by both may also be employed.

[0033] A junction box 48 is provided between the battery 43 and the first inverter 46 (motor generator 41) and the second inverter 47 (electric motor 42) (see FIG. 4). The junction box 48 has relays for switching the electrical connections between the battery 43 and each of the first inverter 46 and the second inverter 47 between a connected state and a disconnected state.

[0034] Junction box 48 also has a relay for switching between a connected state and a disconnected state the electrical connection between first inverter 46 and second inverter 47, in other words, the electrical connection between motor generator 41 and electric motor 42. When motor generator 41 and electric motor 42 are electrically connected to each other, it becomes possible to supply electric power generated by motor generator 41 to electric motor 42. Note that a configuration may be adopted in which each relay is provided individually, without providing junction box 48.

[0035] In the above configuration, the electric motor 42 is driven by power supplied from at least one of the battery 43 and the motor generator 41. The motor generator 41 can supply power to the electric motor 42 while charging the battery 43. The battery 43 can supply power to the motor generator 41 and the electric motor 42 simultaneously. The first inverter 46, the second inverter 47, and the junction box 48 are provided in predetermined locations in the traveling machine body 2.

[0036] The motor generator 41 is connected to the transmission 22 so as to be able to transmit power thereto. The motor generator 41 is disposed behind the transmission 22. However, the location of the motor generator 41 is not particularly limited.

[0037] When functioning as a motor, the motor generator 41 assists the output of the engine 20 via the transmission 22. When functioning as a generator, the motor generator 41 generates electricity by rotating using the driving force from the engine 20 transmitted via the transmission 22. Power is transmitted from the engine 20 to the motor generator 41, for example, so that the rotation speeds of both are the same. The electric power generated by the motor generator 41 is supplied to at least one of the battery 43 and the electric motor 42 via a first inverter 46 and a junction box 48.

[0038] The electric motor 42 is disposed above the rear axle case 28 at a position to the right of the center in the left-right direction, and is supported by the vehicle frame 7 or the like. However, the position where the electric motor 42 is disposed is not particularly limited.

[0039] The motor generator 41 and the electric motor 42 may be connected to each other so that power can be transmitted between them via a switching mechanism such as a clutch that switches between on and off of power. With this configuration, for example, if a problem occurs with the electric motor 42, the planting device 3 can be driven using the output of the engine 20 instead of the output of the electric motor 42. Furthermore, the driving force of the electric motor 42 can assist the output of the engine 20 in addition to the assistance of the engine 20 by the motor generator 41.

[0040] The planting device 3 will now be described. The planting device 3 is supported on the rear side of the traveling body 2 and functions as a ground working unit that plants seedlings in the paddy field surface 6 of the farm field 5. The planting device 3 is connected to the rear of the traveling body 2 via a lifting link mechanism 4 (see Figure 1) to the machine frame 7 so that it can be raised and lowered.

[0041] The lifting link mechanism 4 has a top link 61 extending in the front-rear direction and a pair of left and right lower links 62. The front side of each link is rotatably connected to a vertical link frame 63, and the rear side of each link is rotatably connected to a hitch bracket 64 provided on the front side of the planting device 3. The vertical link frame 63 is erected on the rear axle case 28 at the rear end of the traveling body 2 and is connected to the rear of the rear frame section 12.

[0042] The base end (front side) of a hydraulic lifting cylinder 65 is supported on the upper side of the connecting frame 29 so as to be able to rotate up and down (see Figure 1). The lifting cylinder 65, together with the lifting link mechanism 4, constitutes a lifting device that raises and lowers the planting device 3 relative to the traveling body 2. The tip end (rear side) of the lifting cylinder 65 is connected to the front end of the lower link 62. As the lifting cylinder 65 extends and retracts, each link of the lifting link mechanism 4 rotates up and down, raising and lowering the planting device 3. That is, as the lifting cylinder 65 extends, the planting device 3 descends, and as the lifting cylinder 65 retracts, the planting device 3 rises. The extension and retraction of the lifting cylinder 65 is controlled by controlling the hydraulic flow rate discharged from a hydraulic pump driven by power output from the engine 20.

[0043] The planting device 3 comprises a planting frame 71 connected to the rear side of the lifting link mechanism 4, a planting transmission case 72, a seedling carrier 73 supported by the planting frame 71, and a seedling planting device 80 driven by power transmitted from the planting transmission case 72.

[0044] The planting frame 71 is composed of multiple frame members, such as multiple vertical frames and horizontal frames, and is configured to have a roughly frame-like shape when viewed from the front. The planting frame 71 has a main frame 75 as a horizontal frame attached to its lower part. The main frame 75 is a linear frame member with a rectangular cylindrical outer shape with a roughly square cross section, and is installed horizontally so as to extend in the left-right direction. The main frame 75 is located below the seedling carrier 73 and is installed across almost the entire left-right range of the planting device 3.

[0045] The planting transmission case 72 is provided in the center of the left and right sides of the main frame 75. The planting transmission case 72 is provided in an overhanging shape so that its rear portion is positioned on the rear side of the main frame 75, and has an overhanging portion to the rear.

[0046] The planting transmission case 72 receives the driving force of the electric motor 42 via a transmission shaft 76. The planting transmission case 72 incorporates a power transmission mechanism composed of a gear train including gears such as bevel gears, and the input shaft 72a protrudes forward. The electric motor 42 has its output shaft 42a protrude toward the rear.

[0047] The front end of the transmission shaft 76 is connected to the output shaft 42a of the electric motor 42 via a universal joint 77. The rear end of the transmission shaft 76 is connected to the input shaft 72a of the planting transmission case 72 via a universal joint 78. A transmission device composed of speed increasing / decreasing gears, a speed change mechanism, etc. may be provided between the electric motor 42 and the planting transmission case 72.

[0048] The seedling carrier 73 is located above the planting transmission case 72 and behind the planting frame 71. The seedling carrier 73 has a surface on its front side (upper rear side) for receiving a seedling mat (not shown), and the surface is sloped downward toward the rear. The planting device 3 according to this embodiment has an eight-row planting configuration and has eight seedling carrier sections 79 lined up in the left-right direction (see Figure 2).

[0049] The seedling carrier 73 supplies seedling mats placed on each seedling carrier section 79 to each planting unit. The seedling carrier 73 is configured to be able to move back and forth in the left and right direction by a drive mechanism (lateral feed mechanism) not shown in the figure, so that the seedling mats are continuously fed back and forth in the left and right direction. A vertical feed mechanism is provided for the seedling carrier 73, which feeds the seedling mats on each seedling carrier section 79 vertically downward when the seedling carrier 73 reaches the left and right ends of its reciprocating movement. These horizontal feed mechanisms and vertical feed mechanisms are driven by power transmitted to the planting transmission case 72.

[0050] The seedling planting device 80 is a rotary-type planting device that has a planting transmission case 81, two rotary cases 82 as planting rotors supported on both the left and right sides of the planting transmission case 81, and a planting claw device 90 provided for each rotary case 82. The planting device 3 has eight rotary cases 82, corresponding to an eight-row planting configuration. On both the left and right sides of the planting transmission case 81, the rotary cases 82 and the two planting claw devices 90 form a planting unit.

[0051] The planting transmission case 81 has a cylindrical outer shape with the longitudinal direction being the front-to-rear direction, and its front end is fixed to the rear surface of the main frame 75, extending horizontally from the rear side of the main frame 75 toward the rear. A planting transmission case 81 is provided for every two rows, and there are four planting transmission cases 81 in the eight-row planting rice transplanter 1. The four planting transmission cases 81 are arranged at approximately equal intervals in the left-to-right direction.

[0052] The planting transmission case 81 receives power from the planting transmission case 72 via a planting transmission shaft 85 whose axial direction is in the left-right direction. In other words, the planting transmission shaft 85 interlocks and connects the power transmission mechanisms in each of the planting transmission cases 72 and 81. The planting transmission shaft 85 is rotatably supported relative to the planting transmission case 72 at a position behind the main frame 75, passing through the rear of the planting transmission case 72. The planting transmission shaft 85 is installed between the front parts of the four planting transmission cases 81, and is rotatably supported relative to the planting transmission cases 81, passing through each planting transmission case 81, extending in the left-right direction.

[0053] A pair of rotary cases 82 (two rows) are provided on both the left and right sides of the rear of the planting transmission case 81. The rotary cases 82 are rotatably attached to the planting transmission case 81 by a drive shaft 86 whose axial direction is in the left-right direction (see Figure 6). The drive shaft 86 protrudes to the left and right sides from the planting transmission case 81, and supports the left and right rotary cases 82 rotatably relative to the planting transmission case 81.

[0054] The rotary case 82 has a longitudinal outer shape, and its longitudinal center is axially supported by the planting transmission case 81. Two planting claw devices 90 are attached to the left and right outer sides of the rotary case 82. The two planting claw devices 90 are arranged on opposite sides of the rotary case 82 with respect to the position of the drive shaft 86, and are provided at both longitudinal ends of the rotary case 82.

[0055] The planting claw devices 90 are supported on both longitudinal ends of the rotary case 82 so as to be rotatable about a rotation axis 87 whose rotation axis is in the left-right direction (see Figure 6). The planting claw devices 90 are connected to the rotary case 82 so as to be linked to the rotation of the rotary case 82 relative to the planting transmission case 81. The planting claw devices 90 are configured to perform a predetermined planting operation in conjunction with the rotation of the rotary case 82. By performing the planting operation, the planting claw devices 90 sequentially scrape off the seedling mat placed on the seedling carrier 73 one by one and plant them in the field. With one rotation of the rotary case 82, the two planting claw devices 90 cut seedlings one by one from the seedling mat placed on the seedling carrier 73 and plant them in the paddy field 6.

[0056] As shown in FIG. 6, the planting claw device 90 has an arm 91, a planting claw 92 fixed to the arm 91, and a pusher member 93 movable relative to the arm 91. The planting claw device 90 has a base 90a as the connection portion to the rotary case 82, and an extension portion in which the arm 91, planting claw 92, etc. extend linearly from the base 90a in a predetermined direction, with the tip of the planting claw 92 being the tip of the extension portion. Hereinafter, the direction along the extension direction of the extension portion of the planting claw device 90 will be referred to as the "claw extension direction." In addition, in the planting claw device 90, the tip side of the planting claw 92 in the claw extension direction will be referred to as the front side, and the opposite side will be referred to as the rear side.

[0057] The arm portion 91 is a substantially cylindrical portion whose cylindrical axis direction is the claw extension direction of the planting claw device 90. The arm portion 91 is an integral part of the base portion 90a and extends from the base portion 90a in the claw extension direction.

[0058] The planting claw 92 has a roughly rectangular plate-shaped claw base 92a and a bifurcated claw body 92b extending forward from one longitudinal side of the claw base 92a along the claw extension direction. The planting claw 92 has a roughly constant width overall, with the width direction being the left-right direction and the length direction being aligned with the claw extension direction. The planting claw 92 has the claw base 92a fixed to the upper side of the arm 91 by two fixing parts 96. The fixing parts 96 are fastening fixing parts that protrude upward from the arm 91 and have male threads that penetrate the claw base 92a and have nuts threaded into them. The planting claw 92 has a sharpened tip 92c of the claw body 92b.

[0059] The pusher member 93 is provided on the front side of the arm portion 91 and is configured to move back and forth along the claw extension direction relative to the arm portion 91. The pusher member 93 is provided below the claw body portion 92b of the planting claw 92. The pusher member 93 has a push rod portion 93a and a pressing piece portion 93b provided on the tip side of the push rod portion 93a.

[0060] The push rod portion 93a is a rod portion that forms a cylinder mechanism together with the arm portion 91, with the arm portion 91 serving as the cylinder portion, and extends from the tip of the arm portion 91 in the claw extension direction. The push rod portion 93a moves back and forth relative to the arm portion 91 so as to change the amount of protrusion from the arm portion 91. The pressing piece portion 93b is a portion that moves integrally with the push rod portion 93a relative to the arm portion 91, and is the portion that applies pressure to the seedling blocks scraped from the seedling mat.

[0061] The pusher member 93 is arranged to move back and forth relative to the arm portion 91 between a holding position, which is the rear end position, and a pushing position, which is the front end position. The holding position of the pusher member 93 is the standby position of the pusher member 93 in the planting claw device 90, where it holds the picked seedlings. The pushing position of the pusher member 93 is the forward end position of the pusher member 93 relative to the arm portion 91, where the planting claw device 90 has pushed out (released) the seedling blocks. The pusher member 93 is arranged to move forward relative to the arm portion 91 with a biasing force, pushing out the seedling blocks in a manner that ejects them.

[0062] In the above configuration, the rotational power generated by the electric motor 42 is transmitted to the rotary case 82 via the transmission shaft 76, the planting transmission case 72, the planting transmission shaft 85, and the planting transmission case 81. That is, the planting device 3 receives driving force from the electric motor 42 via the transmission shaft 76 in the planting transmission case 72, and the driving force input to the planting transmission case 72 is transmitted to the planting transmission shaft 85 by a power transmission mechanism within the planting transmission case 72. The rotational driving force of the planting transmission shaft 85 is distributed to the four seedling planting devices 80 and transmitted to the drive shafts 86 of the rotary cases 82 on both the left and right sides of the planting transmission case 81 via multiple transmission shafts, gears, etc. provided within the planting transmission case 81. The rotational driving of the drive shafts 86 rotates the left and right rotary cases 82, allowing the planting claw devices 90 to continuously plant seedlings. In this embodiment, eight rotary cases 82 for eight rows rotate synchronously, and eight rows are planted simultaneously.

[0063] As shown by the dashed line in Figure 6, each planting claw device 90 rotates along a trajectory A1 at the tip 92c of the planting claw 92 as the rotary case 82 rotates, scraping the seedling mat and planting the seedling blocks in one cycle. The trajectory A1 is a closed (loop-shaped) trajectory with a vertically elongated, approximately elliptical shape. The trajectory A1 is the trajectory of the body of the rice transplanter 1, i.e., it does not take into account the movement of the planting claw 92 relative to the field as the body moves forward, and is a stationary trajectory based on the body.

[0064] In the left side view shown in Figure 6, the tip 92c of the planting claw 92 moves counterclockwise on trajectory A1 (see arrow B1). Trajectory A1 is a common trajectory for the two planting claw devices 90 supported on the rotary case 82. The rotary case 82 rotates as the machine body moves forward, planting seedlings continuously in a line with a predetermined spacing between plants (seedling planting intervals) using the two planting claw devices 90.

[0065] As shown in Figure 5, the rice transplanter 1 is equipped with a control device 50 as a control unit. The control device 50 controls each unit of the rice transplanter 1 based on input signals from various sensors and the like equipped in the rice transplanter 1. The control device 50 is configured by connecting, via a bus or the like, a CPU (Central Processing Unit) as an arithmetic processing device that constitutes an arithmetic unit that executes various arithmetic processes and controls, a storage device that constitutes a storage unit such as a RAM (Random Access Memory) or a ROM (Read Only Memory), an input / output device (input / output circuit) that constitutes an input / output unit such as an input / output interface for data input / output, and peripheral circuits such as a clock circuit. The CPU of the control device 50 performs arithmetic processes according to various programs stored in the ROM or the like.

[0066] The control device 50 is configured to include, for example, a plurality of microcomputer units connected to each other so that they can communicate with each other via a controller area network (CAN). However, the configuration of the control device 50 is not particularly limited. The control device 50 is provided in a predetermined location in the rice transplanter 1, such as the machine frame 7.

[0067] 5, the rice transplanter 1 has an operating device 101, a phase detection sensor 102 as a phase detection unit, and a vehicle speed sensor 103, which are electrically connected to an input device (input circuit) of the control device 50. The control device 50 receives input signals from these devices and sensors, and generates a control signal based on the signals.

[0068] The operation device 101 is a device operated by an operator, and includes, for example, operating tools such as levers, switches, dials, and pedals provided on the operation unit 16. When the operation device 101 receives a predetermined operation, it outputs a signal to the control device 50 according to the operation content.

[0069] The phase detection sensor 102 is a sensor for detecting the phase of rotation of the rotary case 82. The phase detection sensor 102 is, for example, a proximity sensor (magnetic sensor) that detects the presence or absence of metal, and detects the phase of rotation of the rotary case 82 (hereinafter simply referred to as "phase") by detecting a protrusion provided on a rotating body such as a rotating shaft that is linked to a transmission mechanism provided inside the planting transmission case 81.

[0070] The phase of the rotary case 82 detected by the phase detection sensor 102 is the angular position of the rotation around the axis of the drive shaft 86 of the rotary case 82 relative to the planting transmission case 81. The control device 50 detects the phase of the rotary case 82 by receiving the detection signal input from the phase detection sensor 102. The control device 50 can detect the phase of the rotary case 82 as an angular position (amount of rotation) relative to a predetermined reference position (rotation angle = 0°).

[0071] The vehicle speed sensor 103 is a sensor for detecting the vehicle speed, which is the traveling speed of the traveling machine body 2. The vehicle speed sensor 103 detects the vehicle speed by detecting the rotation speed of a rotating body such as a shaft in a drive device related to the traveling of the machine body, for example.

[0072] The control device 50 receives an input of a detection signal from the vehicle speed sensor 103 and detects the vehicle speed. The control device 50 controls the vehicle speed based on the detection signal from the vehicle speed sensor 103. The control device 50 receives an input of a detection signal regarding the amount of operation of a gear shift operating member such as a gear shift lever or a gear shift pedal, generates control information based on the detection signal, and controls the vehicle speed based on the generated control information.

[0073] As shown in FIG. 5 , a first inverter 46 for controlling the motor generator 41 and a second inverter 47 for controlling the electric motor 42 are connected to the control device 50. The control device 50 controls the first inverter 46 and the second inverter 47. That is, the first inverter 46 controls the operation of the motor generator 41 under the control of the control device 50, and the second inverter 47 controls the operation of the electric motor 42 under the control of the control device 50. The control device 50 obtains information about the motor generator 41 via the first inverter 46 and obtains information about the electric motor 42 via the second inverter 47. The control device 50 controls the operation of various relays included in a junction box 48.

[0074] The control device 50 controls the electric motor 42, which serves as the drive source for the planting device 3, and basically controls the rotation speed of the electric motor 42 in accordance with the amount of operation of a speed change operating member such as a speed change lever. In other words, when the control device 50 controls the drive of the electric motor 42, the rotational power input from the electric motor 42 to the drive shaft 86 of the rotary case 82 in the power transmission system of the planting device 3 changes speed together with the vehicle speed in accordance with the amount of operation of the speed change operating member.

[0075] Therefore, the rotation speed of the rotary case 82, i.e., the planting speed of the planting device 3, changes depending on the vehicle speed. In detail, the faster the vehicle speed, the shorter the rotation period of the rotary case 82, and the slower the vehicle speed, the longer the rotation period of the rotary case 82. This maintains a constant spacing between plants regardless of the traveling speed of the traveling body 2.

[0076] In this way, the control device 50 issues a rotation instruction (rotation speed instruction) according to the vehicle speed to the electric motor 42. With regard to the spacing between rows, the rotation speed of the rotary case 82 can be changed by controlling the rotation speed of the electric motor 42 relative to the vehicle speed, thereby changing the spacing between rows.

[0077] As described above, the rice transplanter 1 comprises a planting device 3 having a rotary case 82 that supports the planting claws 92 and is rotatably arranged, an electric motor 42 for driving the rotary case 82 to rotate, a phase detection sensor 102 for detecting the phase of the rotary case 82, and a control device 50.

[0078] The control device 50 controls the electric motor 42 based on the phase of the rotary case 82 detected by the phase detection sensor 102 in relation to the operation control of the rotary case 82 .

[0079] The control device 50 controls the rotary case 82 to stop rotation by controlling the drive of the electric motor 42, thereby stopping the rotation of the rotary case 82 at a predetermined phase where the planting claws 92 move away from the field surface (paddy field surface 6). Hereinafter, with regard to the control of stopping the rotary case 82 by the control device 50, the phase where the rotation of the rotary case 82 stops is referred to as the "upper stop position."

[0080] FIG. 6 shows the rotary case 82 in the upper stop position. When the rotary case 82 is in the upper stop position, its longitudinal direction is approximately horizontal. When the rotary case 82 is in the upper stop position, the front and rear planting claw devices 90 position the planting claws 92 in the upper and lower middle portions of the rotation range that forms a loop-shaped trajectory. The upper stop position of the rotary case 82 is set from the perspective of preventing the planting claws 92 from contacting the ground when the planting device 3 is lowered or the planting claws 92 from interfering with the seedling carrier 73 when the seedling carrier 73 is fed laterally when the planting device 3 is in a drive-stopped state (when all rows are stopped), which would cause damage to the planting claws 92 or the seedling carrier 73.

[0081] 6, the upper stop position of the rotary case 82 is the phase of the rotary case 82 when one of the two planting claw devices 90 (front and rear) has its tip 92c positioned within a predetermined phase range C1 at the front and middle of the upper and lower parts of the trajectory A1. In other words, one rotation of the rotary case 82 corresponds to one rotation of the planting claws 92 of the planting claw device 90 along the trajectory A1, and the upper stop position of the rotary case 82 is the phase in which one planting claw device 90A of the two planting claw devices 90 has its tip 92c of the planting claw 92 positioned within the phase range C1.

[0082] As shown in FIG. 6, for example, with respect to the upper stop position, if the lowest point on the locus A1 is set to a reference point P1 where the phase of the rotary case 82 (hereinafter referred to as the "rotary phase") is 0°, the phase range C1 corresponding to the upper stop position is set to a range of 240° to 300°. That is, for the points on the locus A1 shown in FIG. 6, point Pa, which defines the position of the start point of the phase range C1, corresponds to a rotary phase of 240°, and point Pb, which defines the position of the end point of the phase range C1, corresponds to a rotary phase of 300°. Note that, for the points on the locus A1, points P2, P3, and P4 correspond to points where the rotary phase is 90°, 180°, and 270°, respectively. FIG. 6 shows a state where the rotary phase is 290°.

[0083] The control device 50 controls the rotary case 82 to stop based on the operation of the operating device 101. That is, the control device 50 controls the rotary case 82 to stop when the operating device 101 performs a predetermined stop operation to stop the drive of the planting device 3. When the operating device 101 performs a predetermined operation to stop the drive of the planting device 3, a signal is output from the operating device 101 to the control device 50. The control device 50 starts to execute the control device 82 to stop when the signal input from the operating device 101 is used as a trigger.

[0084] The operation of the operating device 101 to control the stop of the rotary case 82, that is, the stop operation of the operating device 101, is functionally equivalent to the operation of turning off the planting clutch using a planting clutch lever in a configuration that has a planting clutch for switching the connection / disconnection of rotational power in the power transmission path for the rotary case 82. Therefore, the stop operation of the operating device 101 can be assigned to the "off" operation of an existing planting clutch lever, for example.

[0085] The control device 50 performs stop control (hereinafter referred to as "planting unit stop control") to stop the rotation of the rotary case 82 by varying the deceleration rate of the rotational speed (= rotation number, hereinafter referred to as "motor rotation number") of the electric motor 42 depending on the magnitude of the difference between the phase of the rotary case 82 detected by the phase detection sensor 102 (hereinafter referred to as "detected phase") and a predetermined target phase set as the stop position of the rotary case 82.

[0086] As shown in graph G1 in Fig. 7, in this embodiment, the control device 50 performs planting unit stop control by decelerating the motor rotation speed at a predetermined deceleration rate from a state in which the motor rotation speed is maintained at a constant value, and then reducing the deceleration rate (making the degree of deceleration gentler) to further decelerate and stop the rotation of the rotary case 82. Graph G1 shows the change in the rotation speed command from the control device 50 to the electric motor 42.

[0087] In graph G1 shown in FIG. 7, the vertical axis represents the motor rotation speed [min^-1] (rpm). In graph G1, the horizontal axis represents the rotary phase difference Δθ (=θa-θb), which is the difference between the target phase value θa and the detected phase value θb actually detected by the phase detection sensor 102. The horizontal axis also corresponds to the passage of time. The target phase value θa is a phase value corresponding to the upper stop position, and is set and stored in advance in a storage device or the like in the control device 50. The target phase value θa is set to a predetermined value within a range of, for example, 240° to 300°.

[0088] In graph G1, the intersection of the vertical axis and horizontal axis corresponds to a state where the motor rotation speed is 0 and the actual-to-series error Δθ is 0. In other words, the intersection of the vertical axis and horizontal axis corresponds to a state where the detected phase value θb reaches the target phase value θa and the electric motor 42 stops, i.e., where the rotation of the rotary case 82 stops.

[0089] In the planting unit stop control, the control device 50 first decelerates the motor rotation speed at a first deceleration rate, and then controls the motor rotation speed at a second deceleration rate that is lower than the first deceleration rate. In graph G1 shown in Figure 7, of the sections in which the motor rotation speed is decelerated, the first deceleration section S1, which is the first section, is the section in which the motor rotation speed is decelerated at the first deceleration rate, and the second deceleration section S2, which is the second section, is the section in which the motor rotation speed is decelerated at the second deceleration rate. Note that the "deceleration rate" is the ratio of the speed reduction to the time.

[0090] As shown in Figure 7, in the planting unit stop control, a deceleration rate switching rotation speed r2 is set, which is the motor rotation speed at which the deceleration rate of the motor rotation speed is switched from the first deceleration rate to the second deceleration rate. In other words, during the process of deceleration of the motor rotation speed, when the motor rotation speed being decelerated at the first deceleration rate reaches the deceleration rate switching rotation speed r2, the deceleration rate of the motor rotation speed is switched from the first deceleration rate to the second deceleration rate. The values ​​of the first deceleration rate, the second deceleration rate, and the deceleration rate switching rotation speed r2 are each set and stored in advance in a storage device or the like in the control device 50.

[0091] An example of planting unit stop control will be described using graph G1 shown in Fig. 7. In this example, the set value of the target phase value θa is set to 260°.

[0092] As shown in Figure 7, the planting unit stop control is initiated, for example, during planting work by the planting device 3, while the motor rotation speed is maintained at a constant rotation speed r1 corresponding to the vehicle speed (see section S0). That is, in section S0, the electric motor 42 rotates at a constant rotation speed r1 based on a rotation command corresponding to the vehicle speed from the control device 50. The end point of section S0, i.e., the control start time t1 of the planting unit stop control, is the timing when the stop operation of the operating device 101 is performed as a trigger to start the control.

[0093] When a stopping operation of the operating device 101 is performed, the control device 50 first calculates a movement amount α1 required to stop the rotary case 82 at the current rotation speed and phase (control start time t1) based on the first deceleration rate, the second deceleration rate, etc. The calculated movement amount α1 is the amount of rotation (rotation angle) of the rotary case 82 until the rotary phase reaches the target phase from the current detected phase, and corresponds to the current actual difference Δθ. Specifically, for example, if the current detected phase value θb is 320°, the movement amount α1 is the amount of rotation until the rotary phase reaches 260° from 320°, and is 300° (= 40° + 260°) (see FIG. 6).

[0094] Next, a stopping operation start position for stopping the rotary case 82 at the target phase is calculated according to the movement amount α1. Here, the control device 50 calculates the deceleration start time t2, which is the timing to start decelerating the motor rotation speed, from the calculated movement amount α1 based on the first deceleration rate, the second deceleration rate, and the deceleration rate switching rotation speed r2.

[0095] In the example shown in Figure 7, the deceleration start time t2 occurs after time Δt has elapsed since control start time t1 of the planting unit stop control, and during time Δt, the motor rotation speed is maintained at rotation speed r1. The section of time Δt is designated rotation speed maintenance section S3. The rotation speed maintenance section S3 is a section in which, after the start of planting unit stop control, the state in which the vehicle speed and the motor rotation speed (the rotation speed of the rotary case 82) are linked in section S0 continues.

[0096] In this way, the control device 50 controls the motor rotation speed to be maintained at rotation speed r1, which is the motor rotation speed at the control start time t1, from the control start time t1, which is the start time of the planting unit stop control, to the deceleration start time t2, which is the time when the motor rotation speed starts to be decelerated (during the rotation speed maintenance section S3).

[0097] Depending on the control start time t1, the rotation speed holding section S3 may not occur. It is also possible to prevent the rotation speed holding section S3 from occurring, for example, even when the motor rotation speed or vehicle speed is extremely low. If the rotation speed holding section S3 does not exist, the control start time t1 and the deceleration start time t2 will coincide, and the motor rotation speed will begin to decelerate simultaneously with the start of planting unit stop control.

[0098] The control device 50 controls the deceleration rate of the motor rotational speed in accordance with the target-to-actual difference Δθ from the deceleration start time t2 to the rotation stop time t4, when the motor rotational speed becomes zero. That is, the link between the vehicle speed and the motor rotational speed is released, and the motor rotational speed is decelerated and stopped at a predetermined deceleration rate. As shown in FIG. 7 , the control device 50 decelerates the motor rotational speed at a first deceleration rate from the deceleration start time t2 (first deceleration section S1), and at timing t3 when the motor rotational speed reaches the deceleration rate switching speed r2, switches the deceleration rate of the motor rotational speed to a second deceleration rate and continues to decelerate the motor rotational speed at the second deceleration rate until the rotation of the electric motor 42 stops (second deceleration section S2).

[0099] The control for switching the deceleration rate of the motor rotation speed may be performed based on the value of the actual-to-spot difference Δθ. In this case, a value θ1 for switching the deceleration rate is set for the value of the actual-to-spot difference Δθ, which decreases over time during planting unit stop control. The control device 50 switches the deceleration rate of the motor rotation speed from the first deceleration rate to the second deceleration rate on the condition that the value of the actual-to-spot difference Δθ reaches the value θ1 after the control device 50 begins decelerating the motor rotation speed from the deceleration start time t2. The value θ1 of the actual-to-spot difference Δθ is set and stored in advance in a storage device or the like in the control device 50.

[0100] As described above, in the planting unit stop control, the motor rotation speed is decelerated and stopped in two stages using the first deceleration rate and the second deceleration rate, with a relatively rapid deceleration followed by a relatively gradual deceleration to stop the rotary case 82. In addition, in the planting unit stop control, a rotation speed holding section S3 is provided in which the rotation speed r1 at the start of the planting unit stop control is held from the start of control until the motor rotation speed actually starts to be decelerated.

[0101] In the example shown in FIG. 7, the section from the deceleration start time t2 to the rotation stop time t4 (section S1 + section S2) corresponds to an angle range of approximately 270° in terms of the amount of rotation of the rotary case 82. Also in the example shown in FIG. 7, the control section S4 (= section S3 + section S1 + section S2) from the control start time t1 of the planting unit stop control to the rotation stop time t4 corresponds to an angle range of approximately 340° depending on the phase of the rotary case 82 when the stop operation of the operating device 101 is performed. The control section S4 is adjusted to a maximum of approximately 340°, for example, by adjusting the control start time t1.

[0102] In the planting unit stop control, when the length of the control section S4 is within an angle range of approximately 340° in relation to the phase of the rotary case 82, after the control start time t1, that is, after the stop operation of the operating device 101, the pair of planting claw devices 90 may plant seedlings one or two times. Figure 7 shows an example of planting points H1 and H2, which are the timings at which planting is performed by the planting claw devices 90.

[0103] Planting point H1 is the timing when planting is performed by one of the two planting claw devices 90 supported by the rotary case 82, and planting point H2 is the timing when planting is performed by the other planting claw device 90. Therefore, the amount of rotation ΔU of the rotary case 82 between planting point H1 and planting point H2 is 180°.

[0104] After deceleration start time t2, the link between vehicle speed and motor rotation speed is released, so the spacing between plants based on vehicle speed is no longer maintained between planting points H1 and H2 (the spacing becomes wider), but the wider spacing is permitted to prevent so-called seedling waste, in which the planting claw device 90 releases seedlings into the air. In this regard, if gradual deceleration and stop control were performed, such as setting the length of control section S4 to 360° or more, damage to the power transmission mechanism of the planting unit that would occur if the rotation of the rotary case 82 were suddenly stopped could be prevented, but planting would occur three or more times with the link between vehicle speed and motor rotation speed released after deceleration start time t2, meaning that the spacing between plants would be uncontrollable.

[0105] According to the rice transplanter 1 of this embodiment having the above-described configuration, in a configuration in which the rotary case 82 is driven to rotate by the electric motor 42, when the rotation of the rotary case 82 is stopped, it is possible to prevent a sudden large force from acting on the power transmission mechanism of the seedling planting device 80, thereby preventing damage to the components of the power transmission mechanism.

[0106] In a configuration in which the rotary case 82 is driven to rotate by the electric motor 42, if the electric motor 42 is suddenly instructed to rotate at 0 by the stop operation of the operating device 101 or other stop operations, there is a risk of damaging the mechanical parts of the planting device 3. On the other hand, if the rotary case 82 stops too slowly when the electric motor 42 is stopped, this may result in wasted seedlings.

[0107] Therefore, according to the planting unit stop control performed by the control device 50, by controlling the deceleration rate of the motor rotation speed depending on the magnitude of the actual difference Δθ in the rotary phase, an appropriate deceleration state can be obtained depending on the magnitude of the actual difference Δθ, so that the rotary case 82 can be safely stopped at the upper stop position without suddenly stopping the rotation of the rotary case 82, while preventing damage to the mechanical parts of the planting device 3. Furthermore, according to the planting unit stop control, by changing the deceleration rate, it is possible to avoid the control section S4 becoming redundant, thereby suppressing the generation of wasted seedlings due to seedling discarding, etc.

[0108] In addition, in the planting section stop control, the control device 50 decelerates the motor rotation speed at a first deceleration rate in the first deceleration section S1, and then decelerates it at a second deceleration rate in the second deceleration section S2, which is a gentler deceleration rate than the first deceleration section S1, thereby stopping the rotation of the rotary case 82.

[0109] According to this control configuration, it is possible to perform a relatively rapid deceleration in the early stages from the start of deceleration of the motor rotation speed, and a gradual deceleration in the later stages including the timing immediately before the rotary phase becomes the target phase (the rotary case 82 stops). This makes it possible to shorten the time from the start of deceleration of the motor rotation speed to the stop of rotation of the rotary case 82, and to stop rotation of the rotary case 82 in a gradual deceleration state in order to prevent damage to the mechanical parts of the planting device 3.

[0110] In the example of graph G1 shown in Fig. 7, the first deceleration rate and the second deceleration rate are each shown as a constant value, but the deceleration rate in each of the first deceleration section S1 and the second deceleration section S2 does not have to be constant. Also, the number of deceleration sections may be three or more. In this case, the deceleration rate in each of the multiple deceleration sections is controlled to gradually decrease (become smaller) over time from deceleration start time t2.

[0111] In addition, in the planting section stop control, the control device 50 performs control to set up a rotation speed holding section S3 in which the motor rotation speed is held at the rotation speed r1 at the control start time t1 as a section between the control start time t1 and the deceleration start time t2.

[0112] This control configuration extends the period during which the motor rotation speed is maintained in accordance with the vehicle speed compared to when the motor rotation speed deceleration begins at control start time t1, thereby reducing the impact on plant spacing (widening of plant spacing) caused by deceleration of the motor rotation speed. Furthermore, because the period during which the motor rotation speed is maintained in accordance with the vehicle speed is extended, deterioration of planting posture, such as seedling tipping over due to the widening of the hole caused by the planting claws 92 working in the field for a longer period of time when planting is performed with the motor rotation speed decelerated, can be prevented. In this way, by providing the rotation speed maintenance interval S3, it is possible to maintain the target plant spacing and planting posture during planting unit stop control, or to reduce the impact of deceleration on the target plant spacing and planting posture.

[0113] As described above, according to the planting unit stop control of this embodiment, by setting a range in which the deceleration rate is changed depending on the actual phase difference Δθ of the rotary case 82, it is possible to stop the rotary case 82 at an appropriate speed so as not to damage the mechanical parts of the planting device 3, while minimizing waste of scraped seedlings even when the rotary case 82 is rotating at high speed.

[0114] [Another example of planting unit stop control] Another embodiment of the planting unit stop control will be described. In the other embodiment described below, the control device 50 performs control to slow down the motor rotation speed according to the magnitude of the actual phase difference Δθ of the rotary case 82 as the planting unit stop control.

[0115] (Another Example 1) As shown in FIG. 8, another embodiment 1 of the planting unit stop control is an example of deceleration and stop control when the operator performs an operation (hereinafter referred to as "travel stop operation") to reduce the vehicle speed to zero or nearly zero (extremely low speed) after the control start time t1. In graph G2 shown in FIG. 8, the travel stop operation is performed at time t5, after Δta has elapsed since the control start time t1. The travel stop operation is performed, for example, by operating a pedal or lever on the operating unit 16. In the example shown in FIG. 8, the time t5 at which the travel stop operation is performed is a timing before the deceleration start time t2 described above. In other words, the travel stop operation is performed in the middle of the rotation speed maintenance section S3 described above.

[0116] As shown in Figure 8, when a travel stop operation is performed, the electric motor 42, which is driven to rotate in conjunction with the vehicle speed, suddenly reduces its motor rotation speed in line with the vehicle speed (see arrow D1). If planting unit stop control is not performed, the motor rotation speed will drop from rotation speed r1, which corresponds to the vehicle speed, to zero or nearly zero as the vehicle speed decreases, as shown by the dashed-dot line in graph G3, and then stop. In this case, the rotary case 82 will stop rotating before reaching the target phase. For convenience, graph G2 in Figure 8 exaggerates the degree of reduction in motor rotation speed due to a travel stop operation, but in reality, it takes a considerable amount of time for the motor rotation speed to decrease.

[0117] Therefore, in the planting unit stop control of this embodiment, if a travel stop operation is performed after the control start time t1, the control device 50 controls the motor rotation speed to be driven at a predetermined rotation speed that is smaller than the rotation speed r1 for a predetermined time from the time t5 when the travel stop operation was performed, and then controls the motor rotation speed to be decelerated at a predetermined deceleration rate and stopped. In other words, the linked state between the vehicle speed and the motor rotation speed is released, and the motor rotation speed is decelerated and stopped at a predetermined rotation speed and a predetermined deceleration rate.

[0118] Specifically, as shown in FIG. 8, at time t5 when the travel stop operation is performed, the control device 50 suppresses the decrease in the motor rotation speed to set the motor rotation speed to a predetermined low-speed rotation speed r3, and maintains the low-speed rotation speed r3 until the value of the scheduled actual-to-actual difference Δθ reaches a predetermined deceleration start phase value θ3 (low-speed section S5). Then, at time t6 when the value of the scheduled actual-to-actual difference Δθ reaches the deceleration start phase value θ3, the control device 50 starts decelerating the motor rotation speed at a predetermined deceleration rate, and decelerates the motor rotation speed at that deceleration rate until rotation of the electric motor 42 stops (deceleration section S6). Here, the predetermined deceleration rate may be, for example, the same as the second deceleration rate described above. Furthermore, the low-speed rotation speed r3 may be, for example, the same as the deceleration rate switching rotation speed r2 described above.

[0119] In the motor rotation speed deceleration / stop control of this embodiment, the control device 50 sets the motor rotation speed to low-speed rotation speed r3 from time t5 when a travel stop operation is performed, and then, on the condition that the value of the set actual-to-actual difference Δθ has reached a value θ3, decelerates the motor rotation speed at a predetermined deceleration rate until rotation stop time t4. The low-speed rotation speed r3, the predetermined deceleration rate, and the value θ3 of the set actual-to-actual difference Δθ used in this embodiment are set and stored in advance in a storage device or the like in the control device 50.

[0120] As described above, in the planting unit stop control of this embodiment, if a travel stop operation is performed after the operation to stop the operation device 101 has been performed and before the motor rotation speed reaches zero, the following deceleration / stop control is performed. That is, the control device 50 performs two-stage deceleration / stop control, in which the motor rotation speed is reduced to a predetermined low rotation speed r3 at the same time as the vehicle speed reaches zero or approximately zero, and then, from a predetermined timing onwards, the motor rotation speed is decelerated relatively slowly to stop the rotary case 82.

[0121] In this way, in the planting section stop control of this embodiment, a rotation command that is not linked to the vehicle speed is sent to the electric motor 42, which is stopped by the stop operation after the control start time t1, to rotate the electric motor 42 at a predetermined rotation speed and then decelerate at a predetermined deceleration rate, thereby forcibly moving the rotary case 82 to the target phase.

[0122] According to the planting unit stop control of this embodiment, if a travel stop operation is performed after the control start time t1, it is possible to prevent a sudden large force from acting on the power transmission mechanism of the seedling planting device 80, thereby preventing damage to the components of the power transmission mechanism. In other words, even if a travel stop operation is performed after the start of the planting unit stop control, the rotary case 82 can be safely stopped at the upper stop position without suddenly stopping the rotation of the rotary case 82, while preventing damage to the mechanical parts of the planting device 3.

[0123] The motor rotation speed deceleration / stop control of this embodiment may be performed in combination with the control using the first deceleration rate and the second deceleration rate as described above. In this case, for example, while basically controlling the motor rotation speed based on graph G1 shown in Fig. 7, the control device 50 may preferentially control the motor rotation speed based on graph G2 shown in Fig. 8 on the condition that a driving stop operation is performed between control start time t1 and rotation stop time t4.

[0124] (Another Example 2) As shown in Figure 9, another example 2 of planting unit stop control is an example of deceleration and stop control when a travel stop operation is performed before the control start time t1, that is, in section S0. In graph G4 shown in Figure 9, a travel stop operation is performed at time t0, which is Δtb before the control start time t1.

[0125] As shown in Figure 9, when a travel stop operation is performed, the electric motor 42, which is driven to rotate in conjunction with the vehicle speed, suddenly reduces its motor rotation speed in line with the vehicle speed (see arrow E1). If planting unit stop control is not performed, the motor rotation speed will drop from rotation speed r1, which corresponds to the vehicle speed, to zero or nearly zero as the vehicle speed decreases, as shown by the dashed-double-dot line in graph G5, and then stop. In this case, the rotary case 82 will stop rotating before reaching the target phase. For convenience, graph G4 in Figure 9 exaggerates the degree of reduction in motor rotation speed due to a travel stop operation, but in reality, it takes a considerable amount of time for the motor rotation speed to decrease.

[0126] Therefore, in the planting unit stop control of this embodiment, if a travel stop operation is performed before the control start time t1, the control device 50 controls the motor rotation speed, which has been zero or approximately zero, to be driven at a predetermined rotation speed that is smaller than the rotation speed r1 for a predetermined time from the time t5 when the travel stop operation was performed, and then controls the motor rotation speed to be decelerated at a predetermined deceleration rate and stopped. In other words, the linked state between the vehicle speed and the motor rotation speed is released, and the motor rotation speed is decelerated and stopped at a predetermined rotation speed and a predetermined deceleration rate.

[0127] Specifically, as shown in FIG. 9 , if the motor rotation speed is lower than a predetermined low-speed rotation speed r4 at control start time t1, the control device 50 increases the motor rotation speed to the predetermined low-speed rotation speed r4 and maintains the low-speed rotation speed r4 until the value of the target-actual difference Δθ reaches a predetermined deceleration start phase value θ4 (low-speed section S7). Then, at time t7 when the value of the target-actual difference Δθ reaches the deceleration start phase value θ4, the control device 50 starts decelerating the motor rotation speed at a predetermined deceleration rate and continues decelerating the motor rotation speed at that deceleration rate until rotation of the electric motor 42 stops (deceleration section S8). Here, the predetermined deceleration rate may be, for example, the second deceleration rate described above or the same deceleration rate as the deceleration rate in the deceleration section S6 of the first embodiment. The low-speed rotation speed r4 may be, for example, the deceleration rate switching rotation speed r2 described above or the same rotation speed as the low-speed rotation speed r3 of the first embodiment.

[0128] In the motor rotation speed deceleration / stop control of this embodiment, the control device 50 sets the motor rotation speed, which is zero or nearly zero due to a stop operation performed at time t0 before control start time t1, to low-speed rotation speed r4 at control start time t1, and then, on the condition that the value of the set-actual difference Δθ has reached a value θ4, decelerates the motor rotation speed at a predetermined deceleration rate until rotation stop time t4. The low-speed rotation speed r4 and the predetermined deceleration rate, as well as the value θ4 of the set-actual difference Δθ used in this embodiment, are set and stored in advance in a storage device or the like in the control device 50.

[0129] As described above, in the planting unit stop control of this embodiment, if a stop operation is performed on the operating device 101 and then a travel stop operation is performed before the motor rotation speed reaches zero, the following deceleration and stop control is performed. That is, if the motor rotation speed is below the low-speed rotation speed r4, which is a predetermined threshold, at the control start time t1 of the planting unit stop control, the control device 50 increases the motor rotation speed to the low-speed rotation speed r4, maintains the motor rotation speed at the low-speed rotation speed r4 until the magnitude of the eye-to-eye difference Δθ reaches a predetermined value θ4, and then decelerates the motor rotation speed at a predetermined deceleration and stops it.

[0130] In this way, in the planting section stop control of this embodiment, a rotation command that is not linked to the vehicle speed is sent to the electric motor 42, which is stopped by the stop operation before the control start time t1, to rotate the electric motor 42 at a predetermined rotation speed and then decelerate at a predetermined deceleration rate, thereby forcibly moving the rotary case 82 to the target phase.

[0131] According to the planting unit stop control of this embodiment, if a travel stop operation is performed before the control start time t1, it is possible to prevent a sudden large force from acting on the power transmission mechanism of the seedling planting device 80, thereby preventing damage to the components of the power transmission mechanism. In other words, even if a travel stop operation is performed before the start of the planting unit stop control, the rotary case 82 can be safely stopped at the upper stop position without suddenly stopping the rotation of the rotary case 82, while preventing damage to the mechanical parts of the planting device 3.

[0132] Furthermore, because the motor rotation speed is linked to the vehicle speed, the stop phase of the rotary case 82 may not be at the upper stop position when the vehicle is stopped. Even in such a case, the planting unit stop control of this embodiment makes it possible to rotate the rotary case 82 to the upper stop position by increasing the motor rotation speed to the low rotation speed r4 through the stop operation of the operating device 101, minimizing planting where the spacing between plants cannot be controlled.

[0133] The motor rotation speed deceleration / stop control of this embodiment may be performed in combination with the control using the first deceleration rate and the second deceleration rate as described above. In this case, for example, while basically controlling the motor rotation speed based on graph G1 shown in Fig. 7, the control device 50 may preferentially control the motor rotation speed based on graph G4 shown in Fig. 9 on the condition that a driving stop operation is performed before the control start time t1.

[0134] The above-described embodiment is an example of the present invention, and the present invention is not limited to the above-described embodiment. Therefore, even if it is not the above-described embodiment, various modifications are possible depending on the design, etc., as long as they do not deviate from the technical idea of ​​the present invention. Furthermore, the effects described in this disclosure are merely examples and are not limited, and other effects may also be obtained.

[0135] In the above-described embodiment, the control device 50 is configured to execute planting unit stop control using the input of a signal resulting from the stop operation of the operating device 101 as a trigger, but the trigger for starting the planting unit stop control is not particularly limited. For example, if the rice transplanter 1 is configured to enable autonomous travel based on position information received from a positioning satellite, an input signal from a controller of a positioning unit (antenna unit) that receives radio waves from the positioning satellite to measure the position of the rice transplanter 1 may be used as a trigger for starting the planting unit stop control.

[0136] That is, with regard to the planting unit stop control, the instruction unit that instructs the driving of the electric motor 42 of the planting device 3 includes an operating device 101 such as a lever arranged on the operating unit 16, as well as a configuration that can input an instruction signal to a configuration (control device 50) that controls the driving of the electric motor 42, for example, when the rice transplanter 1 is running autonomously. [Explanation of symbols]

[0137] 1. Rice transplanter (transplanter) 2 Running body 3 Planting device (planting section) 42 Electric motor 50 Control device (control unit) 80 Seedling planting device 82 Rotary case (planting rotor) 92 Planting Claw 101 Operating device 102 Phase detection sensor (phase detection section)

Claims

1. A running body and A planting unit supported by the traveling machine body, supporting the planting claws and having a rotatably provided planting rotor; An electric motor for rotating the planting rotor; A phase detection unit that detects the phase of the rotation of the planting rotor; a control unit that controls the electric motor based on the phase detected by the phase detection unit, The control unit controls the electric motor to change the deceleration rate of the rotational speed depending on the magnitude of the difference between the phase detected by the phase detection unit and a predetermined target phase set as a stop position of the planting rotor, as a stop control for stopping the rotation of the planting rotor. transplant machine.

2. In the stop control, the control unit performs control to decelerate the rotation speed at a first deceleration rate and then at a second deceleration rate lower than the first deceleration rate.

2. The transplanter of claim 1.

3. the control unit performs control to maintain the rotation speed at the rotation speed at the start time from the start time of the stop control to the start time of deceleration of the rotation speed. A transplanter according to claim 1 or claim 2.

4. A running body and A planting unit supported by the traveling machine body, supporting the planting claws and having a rotatably provided planting rotor; An electric motor for rotating the planting rotor; A phase detection unit that detects the phase of the rotation of the planting rotor; a control unit that controls the electric motor based on the phase detected by the phase detection unit, The control unit performs a stop control to stop the rotation of the planting rotor, and controls the electric motor to reduce its rotation speed depending on the magnitude of the difference between the phase detected by the phase detection unit and a predetermined target phase set as a stop position of the planting rotor. If the rotation speed is lower than a predetermined threshold value at the start of the stop control, the rotation speed is increased to the threshold value, and the rotation speed is maintained at the threshold value until the magnitude of the difference reaches a predetermined value, and then a control is performed to decelerate the rotation speed. transplant machine.

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