Work vehicles

Abstract

To provide a work vehicle which can suppress decrease in work accuracy when a vehicle body is slipped.SOLUTION: A work vehicle according to one aspect of the embodiment includes: a vehicle body having a drive wheel; a planting device attached to the vehicle body; a drive source for generating power for rotating the drive wheel; a clutch for switching a transmission state of the power generated by the drive source to the planting device; a motor for driving the planting device; and a control device for controlling the clutch and the motor. When the slippage of the vehicle body is not detected, the control device turns the transmission state into ON state and drives the planting device by the power generated by the drive source. When the slippage of the vehicle body is detected, the control device turns the transmission state into OFF state and drives the planting device by the power generated by the motor.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a work vehicle. [Background technology]

[0002] Conventionally, there is known a work vehicle that outputs power generated by an engine via a transmission case to a traveling device and a planting device, which is a working part (see, for example, Patent Document 1). The work vehicle can drive the planting device in accordance with the vehicle speed of the traveling vehicle body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-70653 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if the vehicle body slips in a field where the work vehicle is working, there is a risk that the spacing between seedlings transplanted into the field by a planting device will deviate from the spacing that would be achieved if the vehicle body were not slipping. In other words, if the vehicle body slips, there is a risk that the work accuracy will decrease.

[0005] The present invention has been made in view of the above, and has an object to provide a work vehicle that prevents a decrease in work accuracy even when the traveling vehicle body slips. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, a work vehicle (1) according to one aspect of the embodiment includes a traveling body (2) having drive wheels (10, 11), a planting device (55) attached to the traveling body (2), a drive source (30) that generates power to rotate the drive wheels (10, 11), a clutch (27a) that switches the state of transmission of the power generated by the drive source (30) to the planting device (55), a motor (110) that can drive the planting device (55), and a control device (100) that controls the clutch (27a) and the motor (110). When slippage of the traveling body (2) is not detected, the control device (100) switches the transmission state to an on state to drive the planting device (55) with power generated by the drive source (30), and when slippage of the traveling body (2) is detected, switches the transmission state to a off state to drive the planting device (55) with power generated by the motor (110). [Effects of the Invention]

[0007] According to one aspect of the embodiment, the work vehicle can suppress a decrease in work accuracy when the traveling vehicle body slips. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a side view showing a work vehicle. [Figure 2] FIG. 2 is a plan view showing the work vehicle. [Figure 3] FIG. 3 is a schematic diagram showing a part of the seedling planting device. [Figure 4] FIG. 4 is a block diagram showing a control system centered on the control device of the seedling transplanter. [Figure 5] FIG. 5 is an explanatory diagram of the autonomous driving of the seedling transplanter in a farm field. [Figure 6] FIG. 6 is a flowchart illustrating the drive control of the seedling planting device according to the embodiment. [Figure 7] FIG. 7 is a flowchart illustrating the setting control of the reference end point according to the embodiment. [Figure 8]FIG. 8 is a diagram showing a path along which the seedling transplanter automatically moves straight in a field having a concave shape. [Figure 9] FIG. 9 is a diagram showing a path along which the seedling transplanter automatically moves straight in a field having a concave shape. DETAILED DESCRIPTION OF THE INVENTION

[0009] First, an overview of a work vehicle 1 according to an embodiment will be described with reference to Figures 1 and 2. Figure 1 is a side view showing the work vehicle 1. Figure 2 is a plan view showing the work vehicle 1.

[0010] In the following description, the forward / rearward direction refers to the direction of travel of the work vehicle 1 when traveling straight, with the front side of the traveling direction being defined as "front" and the rear side being defined as "rear." The traveling direction of the work vehicle 1 is the direction from the driver's seat 41 toward the handlebars 35 (steering device) when traveling straight (see Figures 1 and 2).

[0011] The left-right direction is a direction that is horizontally perpendicular to the front-rear direction and defines left and right facing the "front." In other words, when the operator (also referred to as an operator) is seated in the operator's seat 41 and facing forward, the left-hand side is the "left" and the right-hand side is the "right."

[0012] The up-down direction is the vertical direction. The front-rear direction, left-right direction, and up-down direction are perpendicular to each other. Each direction is defined for the convenience of explanation, and the present invention is not limited to these directions.

[0013] In this embodiment, the work vehicle 1 will be described as a riding seedling transplanter 1 that is equipped with a seedling planting unit 4 as a work machine and that receives seedlings in a field. As shown in Figures 1 and 2, the seedling transplanter 1 is equipped with the seedling planting unit 4, which can be raised and lowered via a lifting link mechanism 3 on the rear side of the traveling body 2, to plant seedlings in the field.

[0014] The main body of the fertilizer applicator 5 is disposed on the upper rear side of the traveling body 2. If the work vehicle 1 is not a seedling transplanter 1, it may be provided with a sowing device that supplies seeds as a work device.

[0015] The traveling body 2 is a four-wheel drive vehicle equipped with left and right front wheels 10 and rear wheels 11, which are also driving wheels. On the front side of the main frame 15 that forms the body skeleton of the traveling body 2, there are provided a transmission case 13 that transmits power to the seedling planting section 4 and the like, and a hydraulic continuously variable transmission 14 that outputs rotation generated by the engine 30 to the transmission case 13.

[0016] The engine 30 generates power to rotate the front wheels 10 and rear wheels 11. The power generated by the engine 30 is transmitted to the seedling planting unit 4 via the planting clutch 27a (described later) to drive the seedling planting unit 4.

[0017] The continuously variable transmission 14 is a hydrostatic continuously variable transmission known as an HST (Hydro Static Transmission). In the following, a case where the continuously variable transmission is the HST 14 will be described.

[0018] An auxiliary transmission mechanism 16 is provided within the transmission case 13 to switch the driving mode of the traveling vehicle body 2 between high-speed mode for road driving and low-speed mode for planting seedlings, etc. Front wheel final cases 10a are provided on the left and right sides of the transmission case 13, and front wheels 10 are attached to left and right front axles 10b that protrude outward from front wheel support parts that can change the steering direction of the left and right front wheel final cases 10a.

[0019] In addition, rear wheel gear cases 11a are attached to both the left and right sides of a rear frame 22 (see Figure 2) that is arranged laterally on the rear side of the main frame 15, and rear wheels 11 are attached to left and right rear axles 11b that protrude outward from the rear wheel gear cases 11a, respectively.

[0020] Left and right link support frames 23 that support the lifting link mechanism 3 protrude upward from the upper part of the rear frame 22. A pair of left and right lower link arms 24 are provided below and between the left and right link support frames 23. A hydraulically operated lifting cylinder 25 is provided between the left and right lower link arms 24.

[0021] An upper link arm 26 is provided above the lifting cylinder 25, forming a parallel link mechanism, the lifting link mechanism 3. The left and right lower link arms 24, the lifting cylinder 25, and the other end of the upper link arm 26, each of which has one end connected to the traveling vehicle body 2, are attached to the front of the seedling planting section 4.

[0022] An engine 30 is mounted on the main frame 15. Rotational power of the engine 30 is transmitted to the transmission case 13 via the belt transmission device 21 and the HST 14. The rotational power transmitted to the transmission case 13 is changed in speed by the sub-transmission mechanism 16 inside the transmission case 13, and then separated into running power and externally extracted power. In other words, the running power output from the transmission case 13 is transmitted to the front wheels 10 and the rear wheels 11.

[0023] In addition, the externally extracted power extracted from the rotational power transmitted to the transmission case 13 is transmitted to the planting clutch case 27 provided at the rear of the traveling body 2. The externally extracted power is then transmitted from the planting clutch case 27 to the seedling planting section 4 via the first planting transmission shaft 67 and the planting clutch 27a (see Figure 4).

[0024] The rotational power of the engine 30 is transmitted to a hydraulic pump (not shown). The hydraulic pressure generated by the hydraulic pump is supplied to the HST 14, a power steering mechanism 88 (see FIG. 4) of the handle 35, the lift cylinder 25, etc.

[0025] Left and right drive shafts 42 are provided at the rear of the transmission case 13. Rotational power from the engine 30 is transmitted via the transmission case 13 and the drive shafts 42 to the left and right rear wheel gear cases 11a.

[0026] A side clutch 44 (see FIG. 4) that turns on and off the power transmission to the left and right drive shafts 42 is disposed upstream of the left and right drive shafts 42 in the power transmission direction. As shown in FIG. 1, a side clutch pedal 43a that turns on and off the left and right side clutches 44 is provided at the front lower part of the cockpit 41 and on one of the left and right sides.

[0027] Of the left and right side clutch pedals 43a, when the side clutch pedal 43a on the inside of the turn is depressed to disengage the side clutch 44, and then the steering wheel 35 is operated to make a turn, the drive rotation of the rear wheel 11 on the inside of the turn can be completely cut off.

[0028] A bonnet 39 with an operation panel 38 arranged on top for operating each section is provided on the upper front side of the traveling vehicle body 2. The operation panel 38 is provided with a monitor 86 (see FIG. 4) and the like.

[0029] The bonnet 39 is also provided with a handle 35 for steering the traveling vehicle body 2, a speed change control lever 36 for operating the HST 14 and the seedling planting section 4, and an auxiliary speed change control lever 37 for operating the auxiliary speed change mechanism 16.

[0030] An openable front cover 40 is provided in front of the hood 39. Inside the front cover 40, a fuel tank, a battery, and an interlocking mechanism that rotates the left and right front wheels 10 and the lower sides of the left and right front wheel final cases 10a in response to steering of the handlebars 35 are provided. The front wheels 10 are, for example, steerable wheels that turn in response to steering of the handlebars 35.

[0031] An engine cover 30a that covers the top and sides of the engine 30 is provided behind the hood 39 and above the engine 30, and a pilot's seat 41 where the pilot sits is provided above the engine cover 30a.

[0032] The fertilizer applicator 5 is provided behind the driver's seat 41, at the rear end of the main frame 15. The power of the fertilizer applicator 5 is transmitted by a fertilizer transmission mechanism provided so as to face the fertilizer applicator 5 from one of the left and right rear wheel gear cases 11a.

[0033] Approximately horizontal floor steps 33 are formed on both the left and right sides of the lower part of the engine cover 30a and the hood 39. As shown in Fig. 2, the floor steps 33 are partially lattice-shaped, so that even if mud on the shoes of an operator walking on the floor steps 33 falls off, the fallen mud will fall into the field.

[0034] 2, a rear step 330 is connected to the rear of the floor step 33. The surface of the rear step 330 is preferably provided with an anti-slip finish, for example, with a pattern of multiple protrusions, to prevent feet from slipping during work.

[0035] In addition, on the front side of the traveling body 2 and on both the left and right sides, spare seedling frames 50 are provided, each with a seedling frame support 51 on which multiple spare seedling loading tables 52 are arranged at intervals in the vertical direction, so that work materials such as seedlings and fertilizer bags to be replenished in the seedling planting section 4 can be placed.

[0036] Additionally, a seedling tank 53 for carrying seedlings to be planted in the field is attached to the rear end of the lifting link mechanism 3, along with a sliding mechanism for sliding it left and right. Seedling partition fences 54 that are long in the vertical direction are placed on the seedling tank 53 at predetermined intervals in the horizontal direction. Below the seedling tank 53 is placed a seedling planting device 55 (planting device) that picks up the loaded seedlings and plants them in the field.

[0037] The seedling planting device 55 simultaneously plants eight rows, the same number as the number of rows to be planted separated by the seedling partition fence 54. The seedling planting device 55 has four planting transmission cases 56 arranged at intervals below the seedling tank 53. Each planting transmission case 56 is fitted with a planting rotary 57 that rotates on both the left and right sides of the planting transmission case 56 to pick up seedlings using a planting rod 58 and plant them in the field.

[0038] When the planting clutch 27a is engaged, the transmission state of the power generated by the engine 30 in the seedling planting section 4 is switched on, and the externally extracted power taken out from the transmission case 13 is transmitted to the seedling planting device 55. On the other hand, when the planting clutch 27a is released (disengaged), the transmission state of the power generated by the engine 30 in the seedling planting section 4 is switched off, and the externally extracted power taken out from the transmission case 13 is not transmitted to the seedling planting device 55.

[0039] Specifically, when the planting clutch 27a is engaged, the externally extracted power taken out from the transmission case 13 is transmitted to the seedling planting device 55 by the first planting transmission shaft 67 (first drive shaft), as shown in Figure 3. In other words, the first planting transmission shaft 67 transmits the power generated by the engine 30 to the seedling planting device 55. Figure 3 is a schematic diagram showing a part of the seedling planting device 55.

[0040] The first planting transmission shaft 67 is connected to a power transmission mechanism 68 of the seedling planting device 55 so as to be able to transmit power. The power transmission mechanism 68 is configured to transmit power to the planting rotary 57. The power transmission mechanism 68 includes gears, a rotating shaft, a belt mechanism, and the like.

[0041] The seedling planting device 55 can be driven by a planting motor 110 (motor). Specifically, power generated by the planting motor 110 is transmitted to the seedling planting device 55 by a second planting transmission shaft 111 (second drive shaft). The second planting transmission shaft 111 is connected to the power transmission mechanism 68 so as to be able to transmit power. In other words, the second planting transmission shaft 111 transmits the power generated by the planting motor 110 to the seedling planting device 55. The first planting transmission shaft 67 and the second planting transmission shaft 111 are connected to the power transmission mechanism 68 and are configured to transmit power to the seedling planting device 55.

[0042] 1 and 2, in the fertilizer application device 5, the fertilizer application hopper 70 (fertilizer tank) in which fertilizer is stored is divided into the same number of sections (eight rows in the example shown in FIG. 2) as the number of working rows in the seedling planting section 4. Since the fertilizer application hopper 70 with eight rows is long in the left-right direction, which reduces the convenience of adding fertilizer and attaching and detaching it, it may have a so-called side fertilization structure in which sections divided into four rows are lined up on the left and right.

[0043] A dispensing device 71 having a dispensing section that supplies a set amount of fertilizer is provided for each row below the fertilizer hopper 70. The dispensing section is driven by a dispensing motor 71a. For example, the dispensing section is rotated by the dispensing motor 71a. The dispensing section has a recess that can hold fertilizer. When the recess faces upward, fertilizer enters from the fertilizer hopper 70, and when the recess faces downward, the fertilizer is discharged downward. When the dispensing section is rotated by the dispensing motor 71a, fertilizer is discharged from the fertilizer hopper 70.

[0044] A ventilation duct 72 through which the air carrying the fertilizer passes is provided in the left-right direction below the feeding device 71. A fertilizer application hose 73 that guides the fertilizer to the vicinity of the seedling planting position in the seedling planting section 4 is provided below the feeding device 71. A blower 74 that is operated by an electric blower motor 76 to generate the air carrying the fertilizer is also provided at one end of the ventilation duct 72.

[0045] 1 and 2, a center float 62C that slides on the field surface and two side floats 62L and 62R are provided rotatably about axes below the seedling planting section 4. The center float 62C and the left and right side floats 62L and 62R are sometimes collectively referred to as floats 62.

[0046] In addition, below the seedling planting section 4, and ahead of the float 62, a ground leveling rotor 63 for leveling unevenness in the field is provided. Power is transmitted to the ground leveling rotor 63 from the rear wheel gear case 11a on the other left or right side via a rotor transmission shaft 63a.

[0047] 1, line-drawing markers 65 are provided on both the left and right sides of the seedling planting section 4. One of the markers 65 touches the ground on the field surface to form a groove that serves as a guide for traveling in the next work row (next process). When one of the markers 65 touches the ground, the other moves upward, and when the seedling planting section 4 is raised during rotation, both the left and right sides move upward, and when the seedling planting section 4 is lowered after rotation, one of the markers 65 moves upward and the other moves downward.

[0048] 1 and 2, a center mascot 66 that is long in the vertical direction is provided in the center of the left and right of the traveling vehicle body 2, and in front of the hood 39. By aligning the center mascot 66 with the grooves formed in the field by the left and right line markers 65, it becomes possible to travel in accordance with the work position of the previous work row, improving work accuracy and preventing non-working.

[0049] Depending on the soil quality of the field, the guide lines formed by the left and right line-drawing markers 65 may quickly become buried, causing the guide for going straight to disappear. In such cases, it is advisable to use the left and right side markers 19, which are located forward of the left and right line-drawing markers 65. In other words, by moving the left and right side markers 19 outward and positioning them above the planted seedlings, planting work can be performed in accordance with the planting of the seedlings in the previous work row.

[0050] As shown in FIG. 1, the seedling transplanter 1 is also equipped with a position detection device 150. The position detection device 150 detects the current position and orientation of the seedling transplanter 1. That is, the position detection device 150 detects information about the position of the traveling body 2 and the orientation of the traveling body 2. The position detection device 150 includes, for example, an orientation sensor and positioning means such as a GPS (Global Positioning System) or a GNSS (Global Navigation Satellite System). The position detection device 150 may be composed of multiple devices. The position detection device 150 may include a camera or an ultrasonic sensor, and may acquire a turning position in the field and detect the distance to the turning position.

[0051] For example, the position detection device 150 receives positioning information from the positioning means, creates current position information and direction information of the traveling vehicle body 2 based on the received positioning information, and detects the current position and direction. The position detection device 150 is attached to the mounting stay 59, for example, and disposed above the traveling vehicle body 2.

[0052] A straight-line control program and a turning control program, which are created based on position information from the position detection device 150, are stored in different locations. The straight-line control program is stored, for example, in a straight-line control ECU (Electronic Control Unit) 100a in the position detection device 150, and the turning control program is stored, for example, in a turning control ECU 100b housed in the hood 39. The straight-line control ECU 100a and the turning control ECU 100b are included in a control device 100 (see FIG. 4), which will be described later. The straight-line control ECU 100a and the turning control ECU 100b may be stored in the same ECU.

[0053] Next, the control system of the seedling transplanter 1 will be described with reference to Fig. 4. Fig. 4 is a block diagram showing the control system centered on the control device 100 of the seedling transplanter 1. The seedling transplanter 1 is capable of controlling each part by electronic control, and is equipped with a control device (hereinafter referred to as a controller) 100 that controls each part.

[0054] The controller 100 is provided with a processing section having a CPU (Central Processing Unit) and the like, a memory section such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and an input / output section, which are interconnected to allow signals to be exchanged between them. The memory section stores computer programs and the like for controlling the seedling transplanter 1. The controller 100 performs each function by reading out the computer programs and the like stored in the memory section.

[0055] The controller 100 is connected to, for example, actuators such as a throttle motor 80, hydraulic control valves 81 and 82, a planting clutch actuation solenoid 83, and a side clutch actuation solenoid 84. The controller 100 is also connected to an HST motor 85, a line drawing marker lifting motor 87, a steering motor 95 (steering motor), a differential lock switching motor 96, a planting motor 110, and a payout motor 71a.

[0056] The throttle motor 80 increases or decreases the rotation speed of the output shaft of the engine 30 by operating a throttle that adjusts the amount of air intake into the engine 30. The hydraulic control valve 81 controls the extension and retraction of the lifting cylinder 25. The hydraulic control valve 82 controls the power steering mechanism 88. The power steering mechanism 88 changes the direction of the front wheels 10, which are the steering wheels of the traveling body 2. The planting clutch actuation solenoid 83 actuates the planting clutch 27a. That is, the controller 100 controls the planting clutch 27a by controlling the planting clutch actuation solenoid 83.

[0057] The side clutch actuation solenoid 84 actuates the side clutch 44, which switches the state of power transmission to the rear wheels 11 (see FIG. 1). The side clutch 44 is provided on each of the left and right rear wheels 11, and two side clutch actuation solenoids 84 are provided corresponding to each side clutch 44.

[0058] The HST motor 85 changes the rotation angle of the trunnion of the HST 14, thereby changing the tilt angle of the swash plate of the HST 14. The line drawing marker lifting motor 87 lifts and lowers the line drawing marker 65.

[0059] The steering motor 95 rotates the steering wheel 35. The steering motor 95 is a motor that drives the steering wheel 35 to adjust the steering amount (steering angle) of the front wheels 10 (see FIG. 1) when the traveling vehicle body 2 performs automatic straight driving.

[0060] The differential lock switching motor 96 is a motor that switches between operating and deactivating a differential lock mechanism 97 (hereinafter referred to as the differential lock mechanism) that rotates the left and right running wheels, specifically the left and right front wheels 10, at the same rotational speed. When the differential lock mechanism 97 is engaged, the left and right running wheels rotate at the same rotational speed.

[0061] The planting motor 110 drives the seedling planting device 55 via the second planting transmission shaft 111. Specifically, the planting motor 110 rotates the planting rotary 57. When the power generated by the engine 30 is transmitted in an engaged state, i.e., when the planting clutch 27a is engaged, the planting motor 110 functions as a generator. Specifically, the planting motor 110 generates electricity by transmitting external power extracted from the transmission case 13 via the power transmission mechanism 68 and the second planting transmission shaft 111.

[0062] The planting motor 110 is supplied with power from a storage battery 112 (see FIG. 3). In addition, the power generated by the planting motor 110 is supplied to the storage battery 112. In other words, the storage battery 112 is charged by the power generated by the planting motor 110. The storage battery 112 is, for example, a lithium-ion battery or a nickel-metal hydride battery.

[0063] The feed motor 71a drives a feed section that discharges a set amount of fertilizer from the fertilizer application hopper 70 to below the feed device 71. The feed motor 71a is supplied with power from the storage battery 112, for example.

[0064] The controller 100 is connected to detection devices such as a rotation speed sensor 90, a steering amount sensor 91, and an inclination sensor 92. Two rotation speed sensors 90 are provided corresponding to the left and right rear wheels 11, and detect the rotation speeds of the left and right rear wheels 11, respectively. Note that the rotation speed sensors 90 may also detect the rotation speeds of the left and right front wheels 10.

[0065] The steering amount sensor 91 detects the operating position of the steering wheel 35, which is a steering device, i.e., the steering amount (steering angle) of the front wheels 10. The steering amount sensor 91 is provided, for example, on a shaft connected to a pitman arm. The steering amount is detected in both the left and right directions, with the value when the steering wheel 35 is in a preset straight-ahead position being used as a reference value. The tilt sensor 92 detects the tilt angle of the traveling vehicle body 2 in the fore-and-aft direction.

[0066] A line drawing marker detection sensor 93 is provided for each of the left and right line drawing markers 65, and detects the position of the line drawing marker 65. When the line drawing marker 65 is in a predetermined raised position, the line drawing marker detection sensor 93 detects that the line drawing marker 65 is in a non-working state. When the line drawing marker 65 has descended from the predetermined raised position, the line drawing marker detection sensor 93 detects that the line drawing marker 65 has touched the ground and is in a working state.

[0067] In addition, signals are input to the controller 100 as operation signals from the speed change operation lever 36, the auxiliary speed change operation lever 37, the straight-line mode switch 46, the planting section lifting / lowering switch 47, the reference line setting switch 48, and the like.

[0068] The straight-ahead mode switch 46 is a switch for switching whether or not to execute automatic straight-ahead driving. Specifically, the straight-ahead mode switch 46 is a switch for selecting whether to execute manual operation in which the steering wheel 35 is operated by an operator, or automatic straight-ahead driving in which the steering motor 95 is controlled to operate the steering wheel 35. When the straight-ahead mode switch 46 is "ON," automatic straight-ahead driving can be executed. When the straight-ahead mode switch 46 is "OFF," automatic straight-ahead driving is not performed, and manual operation is performed.

[0069] The planting section lifting / lowering switch 47 is a switch that switches whether to lift or lower the seedling planting section 4. The planting section lifting / lowering switch 47 can be changed to the "up" and "down" positions.

[0070] When the planting unit lifting switch 47 is in the "up" position, the seedling planting unit 4 rises to a predetermined raised position (non-working position) and the seedling planting device 55 stops. When the planting unit lifting switch 47 is in the "down" position, the seedling planting unit 4 descends to a predetermined lowered position (working position) and the seedling planting device 55 operates.

[0071] The reference line setting switch 48 is a switch for setting a reference line R0 that serves as a driving reference for automatic straight-ahead driving. When the reference line setting switch 48 is "ON," it becomes possible to set the reference line R0. The method for setting the reference line R0 will be described later.

[0072] Additionally, the current position information of the machine and the like are input to the controller 100 from the position detection device 150. The controller 100 executes an autonomous driving mode in which the machine performs work while driving automatically.

[0073] Here, autonomous travel in a farm field by the seedling transplanter 1 will be described with reference to Figure 5. Figure 5 is an explanatory diagram of the autonomous travel of the seedling transplanter 1 in a farm field. The controller 100 (see Figure 4) has an automatic straight-ahead mode as an autonomous travel mode in which the steering motor 95 (see Figure 4) is controlled to operate the handlebars 35 (see Figure 4) while feeding back the steering amount of the front wheels 10 (see Figure 1). The seedling transplanter 1 may also be capable of automatic turning, in which the seedling transplanter 1 automatically turns along a turning travel path R2.

[0074] As shown in FIG. 5, in the automatic straight-line mode, the seedling transplanter 1 automatically performs the work of planting seedlings in a farm field while traveling, for example, straight along a planned travel route.

[0075] The seedling transplanter 1 plants seedlings while traveling back and forth within a predetermined work area in the field. Regarding straight-line travel, when the controller 100 executes the automatic straight-line mode, the controller 100 executes the straight-line assist to automatically travel along the set straight-line travel route R1.

[0076] The straight travel path R1 is parallel to a reference line R0, which serves as a travel reference. The reference line R0 is set in the field in accordance with the planting direction of the seedlings. The controller 100 acquires the start position of the straight travel as a reference start point (point A), which is a start reference point. The controller 100 also acquires the end position of the straight travel as a final reference end point (point B), which is an end reference point.

[0077] The controller 100 sets the position where the reference line setting switch 48 is turned "ON," i.e., the position where the reference line setting switch 48 is changed from "OFF" to "ON," as the reference start point. A method for setting the final reference end point will be described later. The reference line setting switch 48 may include switches for setting the reference start point and the final reference end point.

[0078] Then, the controller 100 stores the line segment connecting the reference start point (point A) and the final reference end point (point B) as a reference line R0.

[0079] The reference start point and the reference end point include information about the direction and information about the position. That is, the reference line R0 includes information about the direction and information about the position. Also, the straight driving path R1 includes information about the direction and information about the position.

[0080] The reference line R0 is updated when the reference start point (point A) of straight-ahead driving and the final reference end point (point B) are updated. In addition, the straight-ahead driving path R1 in the next process is set parallel to the updated reference line R0.

[0081] Next, drive control of the seedling planting device 55 according to the embodiment will be described with reference to Fig. 6. Fig. 6 is a flowchart illustrating drive control of the seedling planting device 55 according to the embodiment.

[0082] The drive control of the seedling planting device 55 described below is executed in a state where the seedling planting section 4 has been lowered to a predetermined lowered position.

[0083] The controller 100 calculates a first vehicle speed (S100). The controller 100 calculates the first vehicle speed based on information relating to the position of the traveling vehicle body 2. Specifically, the controller 100 acquires information relating to the position of the traveling vehicle body 2 detected by the position detection device 150, and calculates the first vehicle speed of the traveling vehicle body 2 based on the acquired information.

[0084] Next, the controller 100 calculates a second vehicle speed (S101). The controller 100 calculates the second vehicle speed of the traveling vehicle body 2 based on the rotation speed of the rear wheels 11 detected by the rotation speed sensor 90. For example, the controller 100 calculates the second vehicle speed from the average of the rotation speeds of the left and right rear wheels 11.

[0085] Next, the controller 100 determines whether the difference between the first vehicle speed and the second vehicle speed is equal to or greater than a predetermined value (S102). For example, the controller 100 calculates the difference between the first vehicle speed and the second vehicle speed by subtracting the smaller vehicle speed from the larger of the first and second vehicle speeds. Then, the controller 100 determines whether the difference between the first vehicle speed and the second vehicle speed is equal to or greater than a predetermined value. The predetermined value is a vehicle speed at which it can be determined that the traveling vehicle body 2 has slipped in a farm field. In other words, the controller 100 determines whether the traveling vehicle body 2 is slipping.

[0086] The controller 100 determines that the traveling vehicle body 2 is slipping when the difference between the first vehicle speed and the second vehicle speed is equal to or greater than a predetermined value. Also, the controller 100 determines that the traveling vehicle body 2 is not slipping when the difference between the first vehicle speed and the second vehicle speed is less than the predetermined value.

[0087] If the controller 100 determines that the difference between the first vehicle speed and the second vehicle speed is less than a predetermined value and that the traveling vehicle body 2 is not slipping (S102: No), it engages the planting clutch 27a (S103). That is, the controller 100 switches the power generated by the engine 30 to the seedling planting device 55 in an on state, and switches the state in which the externally extracted power extracted from the transmission case 13 is transmitted to the seedling planting device 55. As a result, the externally extracted power extracted from the transmission case 13 is transmitted to the seedling planting device 55, and the planting rotary 57 rotates using the externally extracted power extracted from the transmission case 13.

[0088] If the controller 100 determines that the difference between the first vehicle speed and the second vehicle speed is equal to or greater than a predetermined value and that the traveling vehicle body 2 is slipping (S102: Yes), it disengages the planting clutch 27a (S104). That is, the controller 100 cuts off the transmission of power generated by the engine 30 to the seedling planting device 55, and prevents the externally extracted power extracted from the transmission case 13 from being transmitted to the seedling planting device 55.

[0089] Next, the controller 100 drives the planting motor 110 (S105). The controller 100 controls the planting motor 110 based on the first vehicle speed. Specifically, the controller 100 controls the number of rotations (rotational speed) of the rotary shaft of the planting motor 110 based on the first vehicle speed so that the seedling planting device 55 plants seedlings in the field at a predetermined spacing between plants. As a result, power is transmitted from the planting motor 110 to the seedling planting device 55, and the planting rotary 57 rotates using the power generated by the planting motor 110.

[0090] In this way, when the controller 100 detects a slip of the traveling body 2, it controls the planting motor 110 based on the first vehicle speed, thereby allowing the seedling planting device 55 to perform planting in accordance with the movement of the traveling body 2. Therefore, even if the traveling body 2 slips, fluctuations in spacing between plants due to the slip are suppressed.

[0091] Next, the setting control of the reference end point according to the embodiment will be described with reference to Fig. 7. Fig. 7 is a flowchart illustrating the setting control of the reference end point according to the embodiment.

[0092] The controller 100 determines whether or not the setting of the reference start point (point A) has been executed (S200). Specifically, the controller 100 determines whether or not the reference line setting switch 48 has been changed from "OFF" to "ON." If the reference line setting switch 48 has been changed from "OFF" to "ON," the controller 100 determines that the setting of the reference start point has been executed.

[0093] If the setting of the reference start point has not been executed (S200: No), that is, if the reference line setting switch 48 is maintained at "OFF", the controller 100 ends this processing.

[0094] When the reference start point has been set (S200: Yes), the controller 100 determines whether the operator has performed a manual termination operation for the reference end point (S201). Specifically, the controller 100 determines whether the reference line setting switch 48 has been changed from "ON" to "OFF." The controller 100 determines that a manual termination operation has been performed when the reference line setting switch 48 has been changed from "ON" to "OFF."

[0095] When a manual termination operation is performed (S201: Yes), the controller 100 sets the current position of the traveling vehicle body 2 as the final reference end point (point B) (S202). Specifically, the controller 100 sets the current position of the traveling vehicle body 2 detected by the position detection device 150 as the final reference end point.

[0096] If the manual termination operation has not been performed (S201: No), the controller 100 determines whether a turning operation has started (S203). For example, the controller 100 determines that a turning operation has started when the planting unit lift switch 47 is changed to the "up" position. The controller 100 may also determine that a turning operation has started when the steering amount of the front wheels 10 is equal to or greater than a predetermined steering amount. The predetermined steering amount is a preset value that can be used to determine that the traveling vehicle body 2 has started turning.

[0097] If a turning operation has not been started (S203: No), the controller 100 measures the travel distance of the traveling vehicle body 2 (S204). Specifically, the controller 100 measures the travel distance of the traveling vehicle body 2 based on the position information of the traveling vehicle body 2 detected by the position detection device 150. If the controller 100 has not started measuring the travel distance of the traveling vehicle body 2, the controller 100 starts measuring the travel distance. For example, the controller 100 starts measuring the travel distance immediately after the reference start point is set.

[0098] Next, the controller 100 determines whether the measured moving distance of the traveling vehicle body 2 is equal to or greater than a predetermined distance (S205). The predetermined distance is a distance set in advance, for example, 5 m.

[0099] If the moving distance of the traveling vehicle body 2 is less than the predetermined distance (S205: No), the controller 100 returns to step S201 and repeats the above processing.

[0100] If the travel distance of the traveling vehicle body 2 is equal to or greater than a predetermined distance (S205: Yes), the controller 100 sets a reference end point (point B) (S206). The controller 100 sets the current position of the traveling vehicle body 2 detected by the position detection device 150 as the reference end point (point B). The controller 100 sets the reference end point every time the traveling vehicle body 2 travels a predetermined distance. In other words, the controller 100 updates the reference end point every time the traveling vehicle body 2 travels a predetermined distance. In this way, the controller 100 automatically sets the reference end point.

[0101] Next, the controller 100 resets the measured movement distance (S207). After resetting the movement distance, the controller 100 returns to step S201 and repeats the above process. Note that if the process proceeds to step S204 after the movement distance is reset, measurement of the movement distance is started again.

[0102] When a turning operation is started (S203: Yes), the controller 100 sets the current reference end point as the final reference end point (point B) (S206). As a result, even if the operator forgets to turn the reference line setting switch 48 "OFF," the final reference end point is automatically set when a turning operation is started.

[0103] If a manual termination operation is performed when the reference end point has been automatically set, the automatically set reference end point is reset (deleted), and the position of the traveling vehicle body 2 at the time of the manual termination operation is set as the final reference end point. Also, if a manual termination operation is performed while the travel distance is being measured, or if a turning operation is started while the travel distance is being measured, the travel distance is reset.

[0104] The predetermined distance may be configurable. For example, the predetermined distance may be set by an operator. The operator can set the predetermined distance according to the field, for example.

[0105] The seedling transplanter 1 includes a traveling body 2, a seedling planting device 55, an engine 30, a planting clutch 27a, a planting motor 110, and a controller 100. The traveling body 2 has front wheels 10 and rear wheels 11. The seedling planting device 55 is attached to the traveling body 2. The engine 30 generates power to rotate the front wheels 10 and rear wheels 11. The planting clutch 27a switches the power transmission state to the seedling planting device 55. The planting motor 110 can drive the seedling planting device 55. The controller 100 controls the planting clutch 27a and the planting motor 110. When slippage of the traveling body 2 is not detected, the controller 100 switches the power transmission state to the on state and drives the seedling planting device 55 with the power generated by the engine 30. When slippage of the traveling body 2 is detected, the controller 100 cuts off the transmission state and drives the seedling planting device 55 with the power generated by the planting motor 110.

[0106] As a result, even if the running body 2 of the seedling transplanter 1 slips, the planting motor 110 can drive the seedling planting device 55 to plant the seedlings in the field, thereby preventing a decrease in work accuracy.

[0107] The seedling transplanter 1 includes a first planting transmission shaft 67 and a second planting transmission shaft 111. The first planting transmission shaft 67 transmits power generated by the engine 30 to the seedling planting device 55. The second planting transmission shaft 111 transmits power generated by the planting motor 110 to the seedling planting device 55.

[0108] This allows the seedling transplanter 1 to transmit power from the engine 30 and the planting motor 110 to the seedling planting device 55 via different paths. Therefore, the seedling transplanter 1 can prevent the power transmission paths from the engine 30 and the planting motor 110 to the seedling planting device 55 from becoming complicated, thereby preventing costs from increasing.

[0109] The seedling transplanter 1 is equipped with a position detection device 150 and a rotation speed sensor 90. The position detection device 150 detects information related to the position of the traveling body 2. The rotation speed sensor 90 detects the rotation speed of the rear wheels 11. The controller 100 detects slippage of the traveling body 2 when the difference between a first vehicle speed calculated based on information related to the position of the traveling body 2 and a second vehicle speed calculated based on the rotation speed is equal to or greater than a predetermined value. If the controller 100 does not detect slippage of the traveling body 2, it does not drive the planting motor 110.

[0110] This allows the seedling transplanter 1 to reduce the power consumed by the planting motor 110 when no slippage is detected.

[0111] When the controller 100 detects a slip of the traveling vehicle body 2, the controller 100 controls the planting motor 110 based on the first vehicle speed, thereby causing the seedling planting device 55 to perform planting.

[0112] As a result, even if the traveling body 2 slips, the seedling transplanter 1 can plant seedlings in the field according to the actual movement of the traveling body 2, and can keep the spacing between plants even. Therefore, even if the traveling body 2 slips, the seedling transplanter 1 can use the seedling mat in the field as planned. Furthermore, the seedling transplanter 1 can prevent the spacing between plants from being too narrow, i.e., the seedlings from being planted too closely, improving seedling growth.

[0113] The planting motor 110 functions as a generator when the seedling planting device 55 is driven by the power generated by the engine 30. The power generated by the planting motor 110 is stored in the storage battery 112.

[0114] As a result, the seedling transplanter 1 can charge the storage battery 112 while driving the seedling planting device 55 with the power generated by the engine 30.

[0115] The seedling transplanter 1 is equipped with a fertilizer applicator 5. The fertilizer applicator 5 is provided on the traveling vehicle body 2 and supplies fertilizer to the field. The fertilizer applicator 5 is equipped with a delivery motor 71a that drives a delivery unit that delivers fertilizer from a fertilizer hopper 70. The delivery motor 71a is supplied with power from a storage battery 112.

[0116] This allows the seedling transplanter 1 to use the power generated by the planting motor 110 efficiently.

[0117] The seedling transplanter 1 includes a steering wheel 35 and a steering motor 95. The steering wheel 35 is provided on the traveling body 2. The steering motor 95 drives the steering wheel 35 when the traveling body 2 performs automatic straight-line movement. The controller 100 updates the reference end point (point B) every time the traveling body 2 travels a predetermined distance.

[0118] As a result, when setting the reference line R0 that serves as the reference for automatic straight-line driving, the seedling transplanter 1 can automatically set the reference end point to match the straight-line driving of the traveling body 2. Furthermore, by updating the reference end point, the seedling transplanter 1 can set the reference line R0 to be longer to match the driving of the traveling body 2 when the straight-line driving required to set the reference line R0 becomes longer. Therefore, the seedling transplanter 1 can improve the accuracy of the reference line R0.

[0119] When a manual end operation is performed, the controller 100 sets the position where the manual end operation is performed as the final reference end point.

[0120] This allows the seedling transplanter 1 to set the final reference end point according to the operator's operation. For example, even if the seedling transplanter 1 automatically sets the reference end point, it can prioritize the operator's operation and set the position where the manual end operation was performed as the final reference end point.

[0121] When the turning operation of the traveling vehicle body 2 is started in a state where a manual end operation has not been performed, the controller 100 sets the current final end point as the final reference end point.

[0122] This allows the seedling transplanter 1 to set the final reference end point even if, for example, the operator forgets to turn the reference line setting switch 48 to "OFF."

[0123] The seedling transplanter 1 according to the modified example may have the following configuration.

[0124] The seedling transplanter 1 may be provided with a clutch on the second planting transmission shaft 111. The clutch is disengaged when the planting motor 110 is not driving the seedling planting device 55. In other words, the clutch is disengaged when the traveling body 2 is not slipping. The clutch is engaged when the planting motor 110 is driving the seedling planting device 55. In other words, the clutch is engaged when the traveling body 2 is slipping. The clutch is engaged and disengaged by a solenoid or the like.

[0125] In this way, when the traveling body 2 is slipping, the seedling transplanter 1 engages the clutch and drives the seedling planting device 55 with the planting motor 110. When the traveling body 2 is not slipping, the seedling transplanter 1 releases the clutch, thereby reducing the load on the engine 30.

[0126] When the seedling transplanter 1 sets the reference start point (point A), it displays on the monitor 86 that it is acquiring the reference end point (point B). This allows the seedling transplanter 1 to inform the operator that it is acquiring the reference end point.

[0127] When the seedling transplanter 1 sets a reference end point (point B) after setting the reference start point, that is, when the traveling body 2 moves a predetermined distance and automatically sets the reference end point, the seedling transplanter 1 displays on the monitor 86 that the reference end point has been set. This allows the seedling transplanter 1 to inform the operator that the reference end point has been set.

[0128] When a manual termination operation is performed and the final reference end point (point B) is set, the seedling transplanter 1 stops the above display on the monitor 86. In other words, the seedling transplanter 1 ends the display on the monitor 86 that the reference end point (point B) is being acquired, or the display on the monitor 86 that the reference end point has been set.

[0129] The seedling transplanter 1 may be capable of changing the reference start point and the final reference end point after setting the reference line R0, i.e., after setting the reference start point (point A) and the final reference end point (point B). For example, the reference line R0 including the reference start point and the final reference end point is displayed on the monitor 86. The operator can change the reference start point and the final reference end point by manipulating the reference start point and the final reference end point displayed on the monitor 86. For example, the operator can extend the reference line R0 by changing the final reference end point.

[0130] This allows the operator to set the reference line R0 in accordance with the actual field. For example, if the length of the route traveled to set the reference line R0 is shorter than the length of another route corresponding to the straight travel route R1, the operator can set the reference line R0 to match the length of the other route by changing the reference start point or the final reference end point.

[0131] After setting the reference line R0, the seedling transplanter 1 can add information about the shape of the field. For example, if part of the field is concave in plan view, as shown in Figure 8, it is possible to set position information about the concave shape. Figure 8 is a diagram showing the path that the seedling transplanter 1 automatically travels in a straight line in a field with a concave shape.

[0132] Furthermore, the seedling transplanter 1 may be capable of changing the distance of the straight travel path R1 from the reference line R0 after setting the reference line R0. Furthermore, the seedling transplanter 1 may be capable of setting an area in the field where the straight travel path R1 is to be changed. In other words, the seedling transplanter 1 may be capable of setting a distance (width) by which the length of the straight travel path R1 is changed in a direction (left-right direction) perpendicular to the straight travel path R1. For example, the area where the straight travel path R1 is to be changed is set by inputting position information of the area where the straight travel path R1 is to be changed.

[0133] For example, the operator can set a straight travel route R1-1 that is shorter in distance than the straight travel route R1 set in accordance with the reference line R0, in accordance with the shape of the field. For example, the shape of the field, the reference line R0, the straight travel route R1, etc. are displayed on the monitor 86 or a terminal device, and the operator can set the straight travel route R1-1 while checking the display screen. This allows the operator to easily set the straight travel routes R1, R1-1 in accordance with the shape of the field.

[0134] Furthermore, as shown in FIG. 9, the seedling transplanter 1 may be capable of automatically traveling in a straight line across a concave area A (e.g., a ridge). FIG. 9 is a diagram showing a path along which the seedling transplanter 1 automatically travels in a straight line in a field having a concave shape. The area A can be set after the reference line R0 is set. For example, the area A is set by inputting the position information of the area A. The area A may also be set by distance. For example, the area A may be set by the distance along the straight traveling path R1 and the distance in the direction perpendicular to the straight traveling path R (left-right direction).

[0135] When traveling in area A, the seedling transplanter 1 raises the seedling planting unit 4 to a predetermined raised position. This prevents the seedling planting unit 4 from coming into contact with ridges or the like when traveling in area A. The seedling transplanter 1 may also be able to set a vehicle speed in area A when traveling in area A. The seedling transplanter 1 may also be able to set a judgment value for preventing the traveling body 2 from tipping over when traveling in area A. For example, the seedling transplanter 1 executes safety control such as stopping the traveling body 2 when the tilt angle of the traveling body 2 exceeds the judgment value.

[0136] The seedling transplanter 1 may cancel the automatic straight-line driving and change to manual operation when traveling through area A. When entering area A, the seedling transplanter 1 may inquire of the operator whether to change from automatic straight-line driving to manual operation, and allow the operator to select whether to travel through area A by automatic straight-line driving or by manual operation.

[0137] The seedling transplanter 1 determines whether or not it is possible to travel through area A based on the position information of the traveling body 2 detected by the position detection device 150, the second vehicle speed detected by the rotation speed sensor 90, the inclination angle of the traveling body 2 detected by the inclination sensor 92, etc.

[0138] If the seedling transplanter 1 cannot travel through area A by automatic straight-line driving, it switches to manual operation. If the seedling transplanter 1 cannot travel through area A by automatic straight-line driving, it may detour around area A, set a route that can be traveled by automatic driving, and automatically travel along the set route. If the seedling transplanter 1 cannot travel through area A by automatic straight-line driving, it may stop the traveling vehicle body 2. The seedling transplanter 1 may allow an operator to select whether to automatically travel along the set route or stop the traveling vehicle body 2. Alternatively, a remote control that can remotely operate the seedling transplanter 1 may allow the operator to select whether to automatically travel along the set route or stop the traveling vehicle body 2. Alternatively, the user's terminal device may display the selection of whether to automatically travel along the set route or stop the traveling vehicle body 2. In this case, various information is transmitted to the terminal device via a communication line circuit such as 5G.

[0139] Further advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. [Explanation of symbols]

[0140] 1. Seedling transplanter (work vehicle) 2 Running vehicle 4 Seedling planting department 5 Fertilizer application equipment 10 Front wheels (drive wheels) 11 Rear wheels (drive wheels) 27a Planting clutch (clutch) 30 Engine (power source) 35 Handle 55 Seedling planting device (planting device) 67 First planting transmission shaft (first drive shaft) 70 Fertilizer hopper (fertilizer tank) 71a Feeding motor 90 RPM sensor 95 Steering motor 100 Controller (control device) 110 Planting motor (motor) 111 Second planting transmission shaft (second drive shaft) 112 Storage battery 150 Position detection device

Claims

1. a traveling vehicle body having drive wheels; A planting device attached to the traveling vehicle body; a drive source that generates power to rotate the drive wheels; A clutch that switches the transmission state of the power generated by the drive source to the planting device; A motor capable of driving the planting device; a control device that controls the clutch and the motor; Equipped with The control device When slippage of the traveling vehicle body is not detected, the transmission state is switched to an ON state to drive the planting device using the power generated by the drive source; When slippage of the traveling vehicle body is detected, the transmission state is switched to a disconnected state and the planting device is driven by the power generated by the motor.

2. A first drive shaft that transmits power generated by the drive source to the planting device; a second drive shaft that transmits the power generated by the motor to the planting device; The work vehicle of claim 1 .

3. a position detection device that detects information regarding the position of the traveling vehicle body; a rotation speed sensor for detecting the rotation speed of the drive wheels; Equipped with The control device detecting the slip when a difference between a first vehicle speed calculated based on the information relating to the position of the traveling vehicle body and a second vehicle speed calculated based on the number of revolutions is equal to or greater than a predetermined value; The work vehicle according to claim 1 , wherein the motor is not driven when the slip is not detected.

4. The work vehicle according to claim 3 , wherein when the control device detects the slip, the control device controls the motor based on the first vehicle speed to cause the planting device to perform planting.

5. The motor functions as a generator when the planting device is driven by the power generated by the drive source, The work vehicle according to claim 1 , wherein the electric power generated by the motor is stored in a storage battery.

6. a fertilizer applicator provided on the traveling vehicle body and configured to supply fertilizer to the field; Equipped with The fertilizer application device is A feeding motor that drives the feeding unit that feeds fertilizer from the fertilizer tank Equipped with The work vehicle according to claim 5 , wherein the payout motor is supplied with power from the storage battery.

7. A handle provided on the traveling vehicle body; When the traveling vehicle body performs automatic straight traveling, a steering motor that drives the steering wheel; Equipped with The control device The work vehicle according to claim 1 , wherein a reference end point of a reference line that serves as a travel reference for the automatic straight-line travel is updated every time the traveling vehicle body travels a predetermined distance.

8. The work vehicle according to claim 7 , wherein the predetermined distance is variable.

9. The work vehicle according to claim 7 , wherein, when a reference end point setting operation is performed by an operator, the control device sets the position where the setting operation is performed as the final reference end point.

10. The work vehicle according to claim 7, wherein the control device sets the current reference end point to the final end point when a turning operation of the traveling vehicle body is started without an operator having performed an operation to set the reference end point.

11. The work vehicle according to claim 9 or 10, wherein the reference start point of the reference line and the final reference end point are changeable after the final reference end point is set.

Images