WO2012057334A1

WO2012057334A1 - Rice planting machine

Info

Publication number: WO2012057334A1
Application number: PCT/JP2011/074969
Authority: WO
Inventors: 疋田　康貴
Original assignee: ヤンマー株式会社
Priority date: 2010-10-29
Filing date: 2011-10-28
Publication date: 2012-05-03
Also published as: KR20130082510A; CN103188927A; KR101485549B1; CN103188927B

Abstract

A rice planting machine comprises: an actuator for changing the speed of the engine and/or the transmission ratio of the HST; a speed change means serving as the operation device for changing the amount of drive of the actuator; a control device connected to both the actuator and the speed change means and changing the speed of the vehicle by changing either the speed of the engine and/or the transmission ratio of the HST by means of the actuator on the basis of the amount of operation of the speed change means; and a maximum speed setting means connected to the control device and serving as the operation device for changing the maximum speed which is the speed of the vehicle when the speed change means is operated the maximum amount.

Description

Rice transplanter

The present invention relates to rice transplanter technology.

Conventionally, a technique for changing the vehicle speed of a rice transplanter has been publicly known (for example, Patent Document 1).
In the conventional rice transplanter, the target vehicle speed is always constant with respect to the depression amount of the shift pedal, which is a shift operation tool that moves forward and backward.
However, when a rice transplanter is traveling at a low speed, such as when loading and unloading a rice transplanter on a truck, or when entering or leaving a farm, the conventional rice transplanter requires a small amount of control of the shift pedal. It was done. Thereby, it was difficult to drive the rice transplanter at a desired vehicle speed according to the scene.

JP 2000-236714 A

The present invention eliminates the need for minute adjustments of the shift pedal according to the scene, such as movement, work, loading and unloading from the truck, and putting in the barn, and can easily realize traveling at a desired vehicle speed according to the scene. Provide a machine.

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

That is, the rice transplanter of the present invention
An actuator for changing the engine speed and / or the gear ratio of the HST;
Transmission means that is an operating tool for changing the drive amount of the actuator;
A control device that is connected to the actuator and the speed change means, and changes the vehicle speed by changing at least one of the rotational speed of the engine and the speed ratio of the HST by the actuator based on an operation amount of the speed change means;
A maximum speed setting means that is connected to the control device and is an operating tool for changing a maximum speed that is a vehicle speed when the speed change means is operated up to a maximum operation amount;
The controller is
The target drive amount of the actuator is calculated based on the operation amount of the speed change means, and the actuator is driven so that the drive amount of the actuator becomes the target drive amount. Change the size to correspond to
By changing the target drive amount of the actuator when the speed change means is operated to the maximum operation amount to a size corresponding to the operation amount of the maximum speed setting means, the maximum speed is set to the maximum speed setting means. Change to a size corresponding to the amount of operation.

In the rice transplanter of the present invention,
The maximum speed setting means can be rotated, and within the rotation range, the variable range for changing the maximum speed corresponding to the amount of change of the rotation angle, and the change of the rotation angle A constant speed region that maintains the maximum speed at a constant value.

In the rice transplanter of the present invention,
The constant speed range has a minimum speed range, a maximum speed range, and a sparse recommended speed range provided between the minimum speed range and the maximum speed range,
The variable range includes a first variable range provided between the minimum speed range and the recommended sparse planting speed range, and a second variable range provided between the recommended sparse planting speed range and the maximum speed.

In the rice transplanter of the present invention,
An actuator for changing the engine speed and / or the gear ratio of the HST;
Transmission means that is an operating tool for changing the drive amount of the actuator;
A control device that is connected to the actuator and the speed change means, and changes the vehicle speed by changing at least one of the rotational speed of the engine and the speed ratio of the HST by the actuator based on an operation amount of the speed change means;
Maximum speed setting means that is connected to the control device and is an operating tool for changing a maximum speed that is a vehicle speed when the speed change means is operated to a maximum operation amount;
A speed fixing means connected to the control device, and being an operating tool for fixing the vehicle speed to a constant value regardless of the operation of the speed change means;
The controller changes the drive amount of the actuator based on the operation amount of the maximum speed setting means when the vehicle speed is fixed by the speed fixing means and the maximum speed setting means is operated. Thus, the vehicle speed fixed by the speed fixing means is changed to a size corresponding to the operation amount of the maximum speed setting means.

In the rice transplanter of the present invention,
When the vehicle speed is fixed by the speed fixing means and the vehicle speed after the change by the maximum speed setting means is a value less than a predetermined speed lower limit threshold, the control device performs the vehicle speed by the speed fixing means. Unpin.

In the rice transplanter of the present invention,
The controller is
When the vehicle speed is fixed by the speed fixing means, the speed fixing is performed when the operation amount of the speed change means decreases to less than a predetermined fixed release lower limit and then increases to the fixed release lower limit. Release the vehicle speed fixed by means,
When the vehicle speed is fixed by the speed fixing means and the operation amount of the speed change means increases to a predetermined unlocking upper limit value, the vehicle speed fixing by the speed fixing means is released,
The fixed release lower limit value is a value smaller than a fixed storage position that is an operation amount of the transmission unit when the speed fixing unit is operated and vehicle speed is fixed.
The fixed release upper limit value is a value larger than the fixed storage position.

In the rice transplanter of the present invention,
When the vehicle speed is fixed by the speed fixing means and the maximum speed setting means is operated, the control device, when the maximum speed setting means is operated, the fixed release lower limit value and a fixed value according to the operation amount of the maximum speed setting means Change the cancellation upper limit.

As the effects of the present invention, the following effects are obtained.

In the present invention, since the vehicle speed (maximum speed) required by the operator can be set by the maximum speed setting means, a small amount of the speed change means corresponding to the scene, such as movement, work, loading / unloading from the truck, and barn. Thus, it is possible to easily implement the rice transplanter at a desired vehicle speed according to the scene.

In the present invention, when setting the maximum speed by rotating the maximum speed setting means, if the maximum speed setting means is rotated within the constant speed range, the maximum speed is a constant value corresponding to the constant speed range. Therefore, it is possible to easily set the maximum speed.

In the present invention, when setting the maximum speed by rotating the maximum speed setting means, the maximum speed corresponding to the minimum speed range, the maximum speed corresponding to the recommended sparse planting speed range, and the maximum speed range It is possible to easily set the corresponding maximum speed.
In addition, the maximum speed of the rice transplanter can be easily set to the maximum speed corresponding to the recommended sparse planting speed range, that is, the optimum maximum speed for sparse planting work, so that the planting accuracy is improved when performing sparse planting work. It is possible.
Further, by providing a recommended vehicle speed setting area such as sparse planting, it is possible to prevent the planting rotor from being crushed.

In the present invention, since the vehicle speed (maximum speed) required by the operator can be set by the maximum speed setting means, a small amount of the speed change means corresponding to the scene, such as movement, work, loading / unloading from the truck, and barn. Thus, it is possible to easily implement the rice transplanter at a desired vehicle speed according to the scene.
Further, the vehicle speed (fixed vehicle speed) fixed by the speed fixing means can be changed only by operating the maximum speed setting means. Therefore, the increase / decrease adjustment of the fixed vehicle speed can be performed smoothly.

In the present invention, when the vehicle speed is fixed by the speed fixing means in the low speed range, and the maximum speed setting means is operated to the low speed side (the side where the vehicle speed decreases), the speed of the rice transplanter is stopped. It is possible to prevent the vehicle speed fixed state from being maintained by the fixing means.

In the present invention, when the operator releases the fixed vehicle speed by operating the speed change means, it is possible to select whether to slow down or speed up the vehicle speed at the time of release.

In the present invention, it is possible to prevent the rice transplanter from suddenly accelerating or decelerating when the fixed vehicle speed is released by operating the speed change means.

The whole side view of the rice transplanter which concerns on one Embodiment of this invention. Schematic when the rice transplanter shown in FIG. 1 is viewed from above. The figure which shows the power transmission structure to a front wheel and a rear wheel in the rice transplanter shown in FIG. The figure which shows the power transmission structure to a planting part in the rice transplanter shown in FIG. (A) is a figure which shows the dashboard periphery of the rice transplanter shown in FIG. 1, (b) The enlarged view of the highest speed setting dial. The block diagram which shows the control apparatus of the rice transplanter shown in FIG. The figure which shows a 1st map. The figure which shows a 2nd map. The figure which shows the relationship between the rotation angle of a shift pedal, the rotation angle of the detection shaft of a pedal potentiometer, the rotation angle of the detection shaft of a motor potentiometer, the rotation speed of an engine, and the vehicle speed of a rice transplanter. The figure which shows a 3rd map. (A) The figure which shows fixed release lower limit βx1, (b) The figure which shows fixed release upper limit βx2. Whole side view of rice transplanter. The figure which shows the structure of the power transmission structure and control inside the mission case of a rice transplanter. The map which shows the relationship between an engine speed and a net average effective pressure. A map showing the relationship between the working speed of the rice transplanter and the overall efficiency of the HMT. The map which shows the relationship between engine speed and NOx concentration. A map showing the relationship between engine speed and engine output. The figure which shows the modification of the power transmission structure inside a mission case, and the structure of control.

1 Rice transplanter 14 Engine 67 Shift pedal 67a Pedal potentiometer 69 Maximum speed setting dial 70 Speed fixing lever 71 Motor 71a Motor potentiometer 80 Control device

(Composition of rice transplanter)
First, the whole structure of the rice transplanter 1 which concerns on one Embodiment of this invention is demonstrated. In the present embodiment, the rice transplanter is an eight-row planter, but this is not particularly limited, and a six-plant or ten-row planter may be used.

As shown in FIG. 1 and FIG. 2, the rice transplanter 1 has a traveling unit 10 and a planting unit 40, so that the planting unit 40 can plant seedlings in the field while traveling by the traveling unit 10. Configured. The planting part 40 is arrange | positioned behind the traveling part 10, and is connected with the rear part of this traveling part 10 via the raising / lowering mechanism 30 so that raising / lowering is possible.

In the traveling unit 10, the engine 14 is provided at the front portion of the vehicle body frame 11 and is covered with a bonnet 15. The transmission case 20 is supported by the front portion of the vehicle body frame 11 and is disposed behind the engine 14. As shown in FIG. 3, a hydraulic-mechanical continuously variable transmission (HMT) 21, a main transmission mechanism 22, a clutch 23, and a braking device 24 are mounted inside the mission case 20.

The HMT 21 is a hydraulic continuously variable transmission (HST) 21a capable of steplessly changing the power from the engine 14, and a planetary gear mechanism capable of combining the power from the engine 14 and the power from the HST 21a. 21b.

The main transmission mechanism 22 can change the power from the HMT 21 in a plurality of stages by changing the combination of gears to mesh with each other.

The clutch 23 switches whether power can be transmitted from the HMT 21 to the main transmission mechanism 22 by being disconnected or connected.
The braking device 24 can brake the rotation of the output shaft of the main transmission mechanism 22.

1 and 3, the front axle case 6 is supported on the front portion of the vehicle body frame 11, and the front wheels 12 are attached to the left and right sides of the front axle case 6. The rear axle case 7 is supported on the rear portion of the vehicle body frame 11, and the rear wheels 13 are attached to both the left and right sides of the rear axle case 7.

The power of the engine 14 is transmitted to the mission case 20, and is transmitted to the left and right front wheels 12 and the left and right rear wheels 13 via the HMT 21 and the main transmission mechanism 22 inside the mission case 20, respectively. 12 and the rear wheel 13 are configured to rotate. Thereby, the traveling unit 10 can travel forward or backward.

As shown in FIG. 1 and FIG. 2, in the traveling unit 10, a driving operation unit 60 is provided in the middle of the vehicle body 11 before and after. A dashboard 61 is disposed in front of the driving operation unit 60. A steering handle 64 is disposed at the center of the left and right of the dashboard 61, and a main transmission lever 65, a key switch 66 (see FIG. 5A), and the like are further disposed on the dashboard 61. A driver's seat 62 is arranged behind the steering handle 64 at the rear of the driving operation unit 60.

Further, around the steering handle 64 and the driver's seat 62 of the driving operation unit 60, there are a speed change pedal 67, a brake pedal 68 (see FIG. 5 (a)), a vehicle body cover 63 having a part of the step for getting on and off, and other parts. Operation tools such as levers and switches are arranged. With these operating tools, it is possible to perform appropriate operations on the traveling unit 10 and the planting unit 40. The detailed configuration of the operation tool will be described later.

In the traveling unit 10, the spare seedling stage 17 is attached to each mounting frame 16 erected from both the left and right sides of the front portion of the vehicle body frame 11, and is arranged on both the left and right sides of the bonnet 15. And a reserve seedling is mounted in the reserve seedling mounting stand 17, and the seedling supply to the planting part 40 is attained.

As shown in FIGS. 1, 2, and 4, in the planting unit 40, the planting mission case 50 is supported near the center of the lower part of the planting frame 49, and the transmission shaft 51 is connected to the planting mission case 50. It extends on both the left and right sides. The four planting transmission cases 46 are respectively extended rearward from the transmission shaft 51 and arranged at appropriate intervals in the left-right direction.

A rotary case 44 is rotatably supported on the left and right sides of the rear end of each planting transmission case 46. The number of the rotary cases 44 is the same as the number of planting strips, that is, eight in this embodiment. Then, the two planting claws 45 are attached to both sides of the rotary case 44 in the longitudinal direction so as to sandwich the rotation fulcrum of the rotary case 44.

A seedling stand 41 is disposed above the planting transmission case 46 in a front and rear inclined state, and is attached to the rear portion of the planting frame 49 so as to be reciprocally movable in the left and right directions via upper and lower guide rails (not shown). It is done. The seedling table 41 can be reciprocated horizontally by the lateral feed mechanism 52.

The seedling mounting bases 41 having a plurality of (eight) seedling mat mounting parts are arranged in the left-right direction so that the respective lower ends face one rotary case 44. Then, the seedling mat is placed on each seedling stage 41, and one seedling can be cut from the seedling mat on the seedling stage 41 by the planting claws 45 when the rotary case 44 rotates.

A seedling vertical feed belt 47 corresponding to the number of strips is provided on the seedling mount 41. The seedling vertical feed belt 47 can be operated so that the seedling mat on the seedling stage 41 is vertically fed by the vertical feeding mechanism 53 every time the seedling stage 41 reaches the stroke end of the left and right reciprocating horizontal feed. It is said.

Then, the motive power of the engine 14 is transmitted to each rotary case 44 via the transmission case 20, the inter-company transmission case 54, the planting transmission case 50, etc., and the rotary case 44 is configured to rotate. Thereby, with the rotation operation of the rotary case 44, the two planting claws 45 can alternately take out the seedlings from the seedling mat on the seedling mount 41 and plant them in the field.

At the same time, the power of the engine 14 is transmitted to the lateral feed mechanism 52 and the vertical feed mechanism 53 via the transmission case 20, the inter-strain shifting case 54, the planting mission case 50, etc. It is configured such that it is reciprocated horizontally and the seedling mat on the seedling table 41 is vertically fed downward by the vertical feed mechanism 53 via the seedling vertical feed belt 47 in accordance with the left and right reciprocating horizontal feed of the seedling table 41. Is done. Thereby, the seedling mat on the seedling placing table 41 is moved to an appropriate position with respect to the planting claws 45.

As shown in FIG. 1 and FIG. 2, in the planting part 40, the drawing marker 48 is supported rotatably on the left and right sides of the planting frame 49. Each of the left and right line drawing markers 48 is stored by being rotated upward with the base end side as a rotation fulcrum, and the tip side is left or left by being rotated downward from this stored state. It is configured so that it can be drawn to the field by protruding rightward.

Also, the above-described lifting mechanism 30 is provided between the traveling unit 10 and the planting unit 40. Specifically, the top link 31 and the lower link 32 are installed between the traveling unit 10 and the planting unit 40, and the lifting cylinder is connected between the lower link 32 and the traveling unit 10. And the planting part 40 can be rotated to the up-down direction with respect to the traveling part 10, that is, can be raised or lowered, by the expansion and contraction operation of the lifting cylinder.

Here, the power transmission mechanism for transmitting power from the engine 14 to the rotary case 44, the lateral feed mechanism 52, and the vertical feed mechanism 53 includes the planting clutch 55 shown in FIG. Accordingly, the power of the engine 14 is transmitted to the seedling vertical feed belt 47 and the rotary case 44 or is not transmitted.

Next, the configuration related to the control of the rice transplanter 1 according to this embodiment will be described.

The shift pedal 67 shown in FIGS. 2, 5 (a), and 6 is an operating tool for changing the vehicle speed of the rice transplanter 1. More specifically, the speed of the engine 14 and the gear ratio of the HMT 21 are changed. It is an operation tool for changing. The transmission pedal 67 is disposed on the lower right side of the dashboard 61.

A pedal potentiometer (pedal operation amount detection device) 67a shown in FIG. 6 is for detecting the depression amount (rotation angle) of the shift pedal 67. The pedal potentiometer 67a is connected to the shift pedal 67 via a link mechanism, and can detect the amount of depression of the shift pedal 67. More specifically, the detection shaft of the pedal potentiometer 67a is rotated according to the depression amount (rotation angle) of the shift pedal 67, and the rotation angle can be detected as the depression amount of the transmission pedal 67.
When the shift pedal 67 is depressed, the pedal potentiometer 67a outputs a pedal signal indicating the depression amount of the shift pedal 67.

The maximum speed setting dial 69 shown in FIGS. 5 (a), 5 (b) and 6 is an operating tool for changing the maximum speed, which is the vehicle speed when the shift pedal 67 is depressed to the limit. The maximum speed setting dial 69 is disposed at a substantially central portion of the dashboard 61 (in front of the steering handle 64).

As shown in FIG. 5B, the maximum speed setting dial 69 can be rotated within a predetermined range (D0 degrees or more and D5 degrees or less).
Of these, (a) the region from D0 to D1 is the minimum speed range Da, (b) the region from D1 to D2 is the first variable region Db, and (c) the region from D2 to D3 is the recommended sparse planting speed The region is Dc, (d) the region from D3 to D4 is the second variable region Dd, and (e) the region from D4 to D5 is the maximum speed region De.

By rotating the maximum speed setting dial 69, the maximum speed of the rice transplanter 1 is changed in the range of Vmax1 to Vmax3.
Regarding the magnitude relationship between Vmax1 to Vmax3, Vmax1 <Vmax2 <Vmax3.

(A) When the maximum speed setting dial 69 is rotated within the minimum speed range Da, the maximum speed of the rice transplanter 1 becomes a constant value Vmax1 regardless of the value of the rotation angle of the maximum speed setting dial 69. .
Vmax1 is a vehicle speed when the rice transplanter 1 travels at a low speed (for example, Vmax1 = 0.30 m / s), such as when entering or leaving the field or storing the rice transplanter 1 (loading and unloading on a truck).

(B) When the highest speed setting dial 69 is rotated within the first variable range Db, the maximum speed of the rice transplanter 1 is changed according to the value of the rotation angle of the highest speed setting dial 69, and Vmax1. It is changed in the range of ~ Vmax2.

(C) When the highest speed setting dial 69 is rotated within the recommended sparse planting speed range Dc, the maximum speed of the rice transplanter 1 is a constant value Vmax2 regardless of the value of the rotation angle of the highest speed setting dial 69. It becomes.
Vmax2 is a vehicle speed when the rice transplanter 1 travels at a medium speed when performing sparse planting work (for example, Vmax2 = 1.4 m / s).

(D) When the maximum speed setting dial 69 is rotated within the second variable range Dd, the maximum speed of the rice transplanter 1 is changed according to the value of the rotation angle of the maximum speed setting dial 69, and Vmax2 It is changed within the range of ~ Vmax3.

(E) When the maximum speed setting dial 69 is rotated within the maximum speed range De, the maximum speed of the rice transplanter 1 becomes a constant value Vmax3 regardless of the value of the rotation angle of the maximum speed setting dial 69. .
Vmax3 is a vehicle speed when the rice transplanter 1 travels at a high speed such as when traveling on the road or when planting work is performed at a high speed (for example, Vmax3 = 1.85 m / s).

When the maximum speed setting dial 69 is rotated, a dial signal indicating the rotation angle (operation amount) of the maximum speed setting dial 69 is output.

The main transmission lever 65 shown in FIGS. 2, 5 (a), and 6 is an operating tool for changing the gear position (transmission ratio) of the main transmission mechanism 22. The main transmission lever 65 is disposed at the left end portion of the dashboard 61 (to the left of the steering handle 64). The main transmission lever 65 is connected to the main transmission mechanism 22 in the mission case 20 via a link mechanism.
The main speed change lever 65 can be changed to a road running position, a planting position, a seeding position, a reverse position or a neutral position.
When the main transmission lever 65 is switched to the road traveling position, the gear position of the main transmission mechanism 22 is changed to high speed. In this case, the rice transplanter 1 can travel at high speed.
When the main transmission lever 65 is switched to the planting position, the gear position of the main transmission mechanism 22 is changed to a low speed. In this case, the rice transplanter 1 can travel at a lower speed than when the gear stage of the main transmission mechanism 22 is at a high speed.
When the main transmission lever 65 is switched to the seeding position, the gear position of the main transmission mechanism 22 is changed to neutral. In this case, the rice transplanter 1 cannot travel.
When the main transmission lever 65 is switched to the reverse position, the gear position of the main transmission mechanism 22 is changed to reverse rotation. In this case, the rice transplanter 1 can move backward.
When the main transmission lever 65 is switched to the neutral position, the gear position of the main transmission mechanism 22 is changed to neutral. In this case, the rice transplanter 1 cannot travel.

The main transmission lever 65 includes an operation position detection switch 65a for detecting an operation position.

The key switch 66 shown in FIG. 2, FIG. 5 (a), and FIG. 6 is an operating tool for starting or stopping the engine 14. The key switch 66 is disposed at the right rear end of the dashboard 61 (right rear of the steering handle 64).

A speed fixing lever 70 shown in FIG. 5A and FIG. 6 is an operating tool for fixing the vehicle speed of the rice transplanter 1 and releasing the vehicle speed fixing. The speed fixing lever 70 is fixed to the shaft of the steering handle 64 and extends toward the right.
The speed fixing lever 70 is rotatable (switchable) to a fixed position, a release position, or a neutral position. The fixed position is a position when the speed fixing lever 70 is rotated backward. The release position is a position when the speed fixing lever 70 is rotated forward. The neutral position is a position approximately between the fixed position and the release position. Even when the speed fixing lever 70 is operated to either the fixed position or the release position, the speed fixing lever 70 is always urged so as to return to the neutral position again.
When the rice transplanter 1 is traveling, the speed fixing lever 70 is switched to the fixed position, so that the vehicle speed of the rice transplanter 1 at this time is fixed.
From the state where the vehicle speed of the rice transplanter 1 is fixed, the speed fixing lever 70 is switched to the release position, whereby the vehicle speed fixation of the rice transplanter 1 is released.
Further, when the brake pedal 68 is operated from the state where the vehicle speed of the rice transplanter 1 is fixed, the vehicle speed fixation of the rice transplanter 1 is released.

The rice transplanter 1 has a configuration for finely adjusting the fixed vehicle speed so that it can be changed after the vehicle speed is fixed when the vehicle speed is fixed (auto-cruise) by the speed fixing lever 70. . A detailed description of such a configuration will be given later.

Further, when the vehicle speed is fixed by the speed fixing lever 70, the rice transplanter 1 fixes the vehicle speed by the speed fixing lever 70 without operating the speed fixing lever 70 to the release position or operating the brake pedal 68. It has the structure for canceling. A detailed description of such a configuration will be given later.

The speed fixing switch 70a shown in FIG. 6 is for detecting that the speed fixing lever 70 has been operated to the fixed position. A micro switch is used as the speed fixing switch 70a. The speed fixing switch 70a can detect that the speed fixing lever 70 is operated to the fixed position by contacting the speed fixing lever 70 operated to the fixed position.

The speed fixing release switch 70b is for detecting that the speed fixing lever 70 has been operated to the release position. A micro switch is used as the speed fixing release switch 70b. The speed fixing release switch 70b can detect that the speed fixing lever 70 is operated to the release position by contacting the speed fixing lever 70 operated to the release position.

A brake pedal 68 shown in FIGS. 5A and 6 is an operating tool for braking the rice transplanter 1. The brake pedal 68 is disposed on the lower right side of the dashboard 61 and on the left side of the speed change pedal 67. The brake pedal 68 is connected to the braking device 24 via a link mechanism. When the brake pedal 68 is depressed, the braking device 24 is activated, and the rotation of the front wheels 12 and the rear wheels 13 of the rice transplanter 1 is braked. Note that the braking device 24 can generate a braking force that can maintain the stopped state of the rice transplanter 1 even on a slope.

The brake operation detection switch 68a shown in FIG. 6 is for detecting that the brake pedal 68 has been operated. A micro switch is used as the brake operation detection switch 68a. The brake operation detection switch 68a can detect that the brake pedal 68 has been depressed by contacting the brake pedal 68 that has been depressed.

The seedling end detection switch 49a shown in FIG. 6 detects that the seedling stage 41 has reached a predetermined position (the end position in the left-right direction). A micro switch is used as the seedling end detection switch 49a. The seedling end detection switch 49a is arranged on the planting frame 49 and can detect that the seedling mounting base 41 has reached a predetermined position by contacting a pressing portion provided on the seedling mounting base 41. it can.

A motor 71 shown in FIG. 4 is an actuator for changing the vehicle speed of the rice transplanter 1.
The motor 71 changes the rotational speed of the engine 14, changes the gear ratio of the HMT 21, switches the connection / disconnection of the clutch 23, and switches the operation of the braking device 24. The motor 71 is connected to the engine 14, the HMT 21 (specifically, the HST 21a), the clutch 23, and the braking device 24 via a link mechanism.

More specifically, the output shaft of the motor 71 is connected to the speed governor 14a of the engine 14 via a link mechanism. The speed control device 14a is driven by the motor 71, and the rotation speed of the engine 14 can be changed.
The output shaft of the motor 71 is connected to the movable swash plate of the HST 21a through a link mechanism. The inclination angle of the movable swash plate is changed by the motor 71, and the gear ratio of the HST 21a can be changed.
The output shaft of the motor 71 is connected to the clutch 23 via a link mechanism. The clutch 71 is disconnected or connected by the motor 71.
The output shaft of the motor 71 is connected to the braking device 24 via a link mechanism. When the braking device 24 is operated by the motor 71, the power output to the front wheels 12 and the rear wheels 13 can be braked. Note that the braking device 24 can generate a braking force that can maintain the stopped state of the rice transplanter 1 even on a slope.

The motor potentiometer 71a is for detecting the rotation angle of the output shaft of the motor 71. The motor potentiometer 71a is connected to the motor 71 via a link mechanism, and can detect the rotation angle of the output shaft of the motor 71. More specifically, the detection shaft of the motor potentiometer 71 a is rotated according to the rotation angle of the output shaft of the motor 71, and the rotation angle can be detected as the rotation angle of the output shaft of the motor 71.

The cell motor 72 is an actuator for starting the engine 14.

The meter panel 73 shown in FIG. 2, FIG. 5, and FIG. 6 is for displaying various information related to the operation of the rice transplanter 1, the engine, the abnormality alarm, and the like. The meter panel 73 is disposed at the approximate center of the left and right of the dashboard 61 and in front of the steering handle 64.

6 is an operating tool for operating the gear position of the inter-company transmission mechanism 75 (see FIG. 4). The inter-strain shifting mechanism 75 changes the planting interval by shifting the planting speed with respect to the vehicle speed. The inter-strain shifting mechanism 75 is configured to be capable of inconstant speed shifting that causes a change in the planting speed during the planting cycle. At the time of sparse planting, seedling dragging can be prevented by operating the inter-strain shifting lever 74 and setting the inter-strain shifting mechanism to a non-uniform speed shifting.

6 is used for detecting that the inter-stock shift lever 74 is at the non-uniform speed shift position. The inconstant speed shift position is the position of the inter-company shift lever 74 at which the inter-company transmission mechanism 75 is in an inconstant speed shift. A micro switch is used as the unequal speed shift operation detection switch 74a. The unequal speed shift operation detection switch 74a is disposed in the vicinity of the unequal speed shift position. The non-uniform speed change operation detection switch 74a can detect that the inter-set speed change lever 74 is in the non-uniform speed shift position by contacting the inter-set speed change lever 74 operated to the non-uniform speed shift position.

The control device 80 inputs a detection signal, and transmits a control signal to the motor 71, the cell motor 72, the meter panel 73, and the like based on the input detection signal and program. In addition, the control device 80 stores information related to various signals.
Specifically, the control device 80 may be configured such that a CPU, a ROM, a RAM, an HDD, and the like are connected by a bus, or may be configured by a one-chip LSI or the like.

The control device 80 is connected to the pedal potentiometer 67a, and can obtain a detection signal (pedal signal) indicating the amount of depression of the shift pedal 67 by the pedal potentiometer 67a.
The control device 80 is connected to the maximum speed setting dial 69 and can acquire a detection signal (dial signal) indicating the rotation angle (operation amount) of the maximum speed setting dial 69.
The control device 80 is connected to the operation position detection switch 65a and can acquire a detection signal indicating the operation position of the main transmission lever 65 by the operation position detection switch 65a.
The control device 80 is connected to the key switch 66, and can acquire a detection signal (start signal) indicating that the start operation has been performed by the key switch 66 and a detection signal (stop signal) indicating that the stop operation has been performed. it can.
The control device 80 is connected to the speed fixing switch 70a, and can acquire a detection signal (fixed signal) indicating that the speed fixing lever 70 by the speed fixing switch 70a has been operated to the fixed position.
The control device 80 is connected to the speed fixing release switch 70b, and can acquire a detection signal (release signal) indicating that the speed fixing lever 70 by the speed fixing release switch 70b has been operated to the release position.
The control device 80 is connected to the brake operation detection switch 68a, and can acquire a detection signal indicating that the brake pedal 68 has been depressed by the brake operation detection switch 68a.
The control device 80 is connected to the seedling end detection switch 49a, and can acquire a detection signal indicating that the seedling stage 41 has reached a predetermined position by the seedling end detection switch 49a.

The control device 80 is connected to the motor 71 and can transmit a control signal to the motor 71 to rotate the motor 71.
The control device 80 is connected to the motor potentiometer 71a, and can acquire a detection signal of the rotation angle of the motor 71 by the motor potentiometer 71a.
The control device 80 can drive the motor 71 to a desired rotation angle by transmitting a control signal to the motor 71 until the detection signal from the motor potentiometer 71a reaches a desired rotation angle.

The control device 80 is connected to the cell motor 72 and can transmit a control signal to the cell motor 72 to drive the cell motor 72.
The control device 80 is connected to the meter panel 73, and can display the information when the operating state or abnormality of the engine or the work machine is detected.

The control device 80 is connected to the inconstant speed shift operation detection switch 74a, and can acquire a detection signal indicating that the stock shift lever 74 is operated to the inconstant speed shift position by the inequal speed shift operation detection switch 74a. .

In addition, when the control device 80 obtains a detection signal indicating that the stock shift lever 74 has been operated to the inconstant speed shift position, the control device 80 limits the drive of the motor 71 so that the vehicle speed becomes low. That is, comparing the case where the control device 80 acquires the detection signal of the inconstant speed position with the case where the control device 80 does not acquire it, if the amount of depression of the shift pedal 67 is the same, the detection signal of the inconstant speed position is acquired. In this case, the motor 71 is rotated to the low speed side. Thereby, at the time of sparse planting work, it is possible to suppress working at high speed and reliably prevent seedling dragging.
In this embodiment, the control device 80 is configured to detect the position when the inter-shaft shift lever 74 is operated to the inconstant speed shift position, but the inter-shaft speed change mechanism 75 does not become inconstant speed, etc. It is also possible to adopt a configuration for detecting the position where the speed is changed. Furthermore, it is also possible to provide a microswitch or the like for each shift stage regardless of the constant speed shift or the non-uniform speed shift, and to limit the driving of the motor for each shift stage. Thereby, it is possible to work at a gear position of the inter-stock transmission mechanism 75, that is, at an optimum speed suitable for the inter-stock.

(First map)
The control device 80 also includes a relationship between the depression amount β of the speed change pedal 67 and the rotation angle γ of the motor 71 (more specifically, the rotation angle β of the detection shaft of the pedal potentiometer 67a and the motor potentiometer. The first map showing the relationship with the rotation angle γ of the detection shaft 71a) is stored.

FIG. 7 shows the first map. In FIG. 7, the horizontal axis indicates the depression amount β of the speed change pedal 67, and the vertical axis indicates the rotation angle γ of the detection shaft of the motor potentiometer 71a.
When the shift pedal 67 is depressed, the control device 80 calculates the rotation angle γ of the motor 71 corresponding to the depression amount β of the shift pedal 67 in the first map as the target rotation angle, and calculates the calculated target rotation. The motor 71 is rotated so as to have a moving angle. Thereby, the vehicle speed of the rice transplanter 1 is changed to a magnitude corresponding to the depression amount β of the shift pedal 67.

The depression amount β of the speed change pedal 67 is configured to vary in the range of β1 to βmax. β1 is the depression amount of the shift pedal 67 when the shift pedal 67 is not depressed and is in a free state. βmax is the depression amount of the shift pedal 67 when the shift pedal 67 is depressed to the limit.

In β on the horizontal axis of the first map, the region from β1 to βmax further includes a play region (β1 or more and less than β2), a connection region (β2), a speed change region (greater than β2 and less than β3), and the highest speed holding. It is divided into regions (β3 or more and βmax or less).

In the play area (β1 or more and less than β2) of the first map, the rotation angle γ of the motor 71 is held at a constant value (γ1).
In the connection area (β2) of the first map, the rotation angle γ of the motor 71 is held at a constant value (γ2).
In the shift region (greater than β2 and less than β3) in the first map, the rotation angle γ of the motor 71 corresponds to β3 from γ2 corresponding to β2 as the depression amount β of the shift pedal 67 increases. Increases to γmax.
In the highest speed holding region (β3 or more and βmax or less) in the first map, the rotation angle γ of the motor 71 is held at a constant value (γmax).

Also, the control device 80 stores a second map indicating the relationship between the rotation angle D of the maximum speed setting dial 69 and the correction ratio PA (corrected target rotation angle of the motor 71) of the motor 71.

(Second map)
FIG. 8 shows the second map. 8, the horizontal axis indicates the rotation angle D of the maximum speed setting dial 69, and the vertical axis indicates the correction ratio PA (corrected target rotation angle of the motor 71) of the target rotation angle γmax of the motor 71. .
When the depression amount β of the speed change pedal 67 is in the maximum speed holding region (β3 or more and βmax or less), when the maximum speed setting dial 69 is rotated, the controller 80 calculates the motor 71 calculated based on the first map. The target rotation angle γmax is corrected (corrected) based on the second map to calculate the corrected target rotation angle.
And the control apparatus 80 changes the maximum speed of the rice transplanter 1 to the magnitude | size according to the rotation angle D of the maximum speed setting dial 69 by rotating the motor 71 so that it may become a correction target rotation angle. To do.
The procedure for calculating the corrected target rotation angle based on the second map will be described in detail in (2-4) described later, and the second map will be described below.

The vertical axis of the second map indicates the correction ratio PA of the target rotation angle γmax of the motor 71. The correction ratio PA indicates the ratio when the target rotation angle γmax of the motor 71 calculated based on the first map is corrected (corrected) according to the rotation angle D of the maximum speed setting dial 69 in terms of a thousandths. It is a thing.

In the rotation angle D of the horizontal axis of the second map, the area from D0 to D5 is further the minimum speed area Da (D0 or more and less than D1), first variable area Db (D1 or more and less than D2), and sparse vegetation recommendation It is divided into a speed range Dc (D2 or more and less than D3), a second variable range Dd (D3 or more and less than D4), and a maximum speed range De (D4 or more and D5 or less).

In the lowest speed range Da (D0 or more and less than D1) in the second map, the correction ratio PA is held at a constant value (VRS ‰).
In the first variable range Db (D1 or more and less than D2) in the second map, the correction ratio PA is (VRSM = {(VRM−VRS) · (D−D1) / (D2−D1)} + VRS ‰). As the rotation angle D of the maximum speed setting dial 69 increases, the rotation speed increases from (VRS ‰) corresponding to the rotation angle D1 to (VRM ‰) corresponding to the rotation angle D2.
In the recommended sparse planting speed range Dc (D2 or more and less than D3) in the second map, the correction ratio PA is held at a constant value (VRM) ‰.
In the second variable range Dd (D3 or more and less than D4) in the second map, the correction ratio PA is (VRSH = {(1000−VRM) · (D−D3) / (D4−D3)} + VRM ‰). As the rotational angle D of the maximum speed setting dial 69 increases, the rotational speed increases from (VRM ‰) corresponding to the rotational angle D3 to (1000 ‰) corresponding to the rotational angle D4.
In the maximum speed range De (D4 or more and D5 or less) in the second map, the correction ratio PA is held at a constant value (1000 ‰).

In the second map, the slope of the second variable region (D3 or more and less than D4) is configured to be smaller than the slope of the first variable region (D1 or more and less than D2) ((1000− VRM) / (D4-D3) <(VRM-VRS) / (D2-D1)).
That is, the second variable region is configured such that the change amount of the correction ratio PA with respect to the rotation angle of the maximum speed setting dial 69 is smaller than that of the first variable region.
Accordingly, when the maximum speed setting dial 69 is rotated, the correction ratio PA is finely adjusted when the maximum speed setting dial 69 is rotated within the second variable range, rather than when it is rotated within the first variable range. Is possible.

(Basic operation of rice transplanter)
In the rice transplanter 1 configured as described above, when the key switch 66 is started, the control device 80 drives the cell motor 72 to start the engine 14. In addition, when the key switch 66 is stopped, the control device 80 rotates the motor 71 to cut off the fuel supply by the speed governor 14a (in this embodiment, an ignition device in the case of a diesel engine or a gasoline engine). The engine 14 is stopped.

Further, when the control device 80 acquires the pedal signal indicating the depression amount of the speed change pedal 67, the control device 80 calculates a target rotation angle of the motor 71 based on the acquired pedal signal. Then, the control device 80 corrects (changes) the calculated target rotation angle based on the dial signal acquired from the maximum speed setting dial 69, thereby calculating the corrected target rotation angle. Then, the control device 80 rotates the motor 71 so that the calculated correction target rotation angle is obtained, thereby changing the rotation speed of the engine 14, changing the speed ratio of the HMT 21, switching the connection / disconnection of the clutch 23, Then, the operation of the braking device 24 is switched, and the vehicle speed of the rice transplanter 1 is changed.

Hereinafter, a configuration when the control device 80 calculates the target rotation angle and the corrected target rotation angle will be described.

(Target rotation angle)
The target rotation angle is calculated based on the depression amount of the speed change pedal 67 (the pedal signal).
Regarding the target rotation angle, when the control device 80 acquires the pedal signal indicating the depression amount of the shift pedal 67, the motor corresponding to the acquired pedal signal (depression amount β of the shift pedal 67) in the first map. The rotation angle γ of 71 is calculated, and the calculated rotation angle γ is set as the corrected target rotation angle γ.

The target rotation angle γ has the following values (1-1) to (1-4) according to the magnitude of the pedal signal (depression amount β of the shift pedal 67) acquired by the control device 80. .

(1-1) As shown in FIG. 7, when the pedal signal acquired by the control device 80 becomes βa (β1 or more and less than β2) (play area), the target rotation angle γ is a constant value (rotation angle). γ1).

(1-2) When the pedal signal acquired by the control device 80 is β2 (connection region), the target rotation angle γ is a constant value (rotation angle γ2).

(1-3) When the pedal signal acquired by the control device 80 is βb (greater than β2 and less than β3) (shift region), the target rotation angle γ is γb corresponding to βb in the first map. (Γ2 or more and less than γmax). Therefore, the target rotation angle γb in this case changes according to the value of the acquired pedal signal (rotation angle βb).

(1-4) When the pedal signal acquired by the control device 80 becomes βc (β3 or more and βmax or less) (maximum speed holding region), the target rotation angle γ becomes a constant value (rotation angle γmax).

(Corrected target rotation angle)
The correction target rotation angle is obtained by correcting the target rotation angle γ calculated in the above (1-1) to (1-4) based on the rotation angle value of the maximum speed setting dial 69 (the dial signal) ( Change).
The corrected target rotation angle has the following values (2-1) to (2-4) according to the depression amount β of the shift pedal 67, that is, the magnitude of the pedal signal acquired by the control device 80.

(2-1) When the pedal signal acquired by the control device 80 is βa (β1 or more and less than β2) (play area), the control device 80 determines the value of the rotation angle D of the maximum speed setting dial 69 (dial Regardless of the signal), the target rotation angle γ1 calculated in (1-1) is set as the corrected target rotation angle.

(2-2) When the pedal signal acquired by the control device 80 becomes β2 (connection region), the control device 80 does not depend on the value (dial signal) of the rotation angle D of the maximum speed setting dial 69. The target rotation angle (rotation angle γ2) calculated in (1-2) is set as the corrected target rotation angle.

(2-3) When the pedal signal acquired by the control device 80 becomes βb (greater than β2 and less than β3) (shift region), the control device 80 calculates the target rotation calculated in (1-3) above. The angle γb is appropriately corrected based on the value (dial signal) of the rotation angle D of the maximum speed setting dial 69. Then, the control device 80 calculates the corrected value as a corrected target rotation angle.

(2-4) When the pedal signal acquired by the control device 80 becomes βc (β3 or more and βmax or less) (maximum speed holding region), the control device 80 sets the target number of times calculated in (1-4) above. The moving angle γmax is corrected based on the value of the rotation angle D (dial signal) of the maximum speed setting dial 69. Then, the control device 80 calculates the corrected value as a corrected target rotation angle.
In the present embodiment, the correction target rotation angle in this case is calculated using the second map shown in FIG. 8, and the following (2-) is calculated according to the rotation angle D of the maximum speed setting dial 69. The values are as shown in (4-1) to (2-4-5).
Hereinafter, this will be described in detail with reference to FIG.

(2-4-1) When the rotation angle D of the maximum speed setting dial 69 is (a) the minimum speed range Da (D0 or more and less than D1), the correction ratio PA in the second map at this time is (VRS ‰). )become. Accordingly, the corrected target rotation angle (γmax1) at this time, that is, the maximum rotation angle of the motor 71 is a value shown in the following [Equation 1], which is a constant value. In the present embodiment, the rotation angle γ of the motor 71 when the correction ratio PA is (0 ‰) is set to the rotation angle γ2.
[Equation 1]
γmax1 = {(γmax−γ2) × VRS / 1000} + γ2

(2-4-2) When the rotation angle D of the maximum speed setting dial 69 is (b) the first variable range Db (D1 or more and less than D2), the correction ratio PA in the second map at this time is the rotation Depending on the value of the angle D, it becomes any value within the range of (VRS ‰ to VRM ‰). Therefore, the corrected target rotation angle (γmax2) at this time, that is, the maximum rotation angle of the motor 71 is a value shown in the following [Equation 2], and changes corresponding to the value of the rotation angle D.
[Equation 2]
γmax2 = {(γmax−γ2) × VRSM / 1000} + γ2
VRSM = {(VRM−VRS) · (D−D1) / (D2−D1)} + VRS

(2-4-3) When the rotation angle D of the maximum speed setting dial 69 is (c) the sparse planting recommended speed range Dc (D2 or more and less than D3), the correction ratio PA in the second map at this time is ( VRM ‰). Therefore, the corrected target rotation angle (γmax3) is a value shown in the following [Equation 3], which is a constant value.
[Equation 3]
γmax3 = {(γmax−γ2) × VRM / 1000} + γ2

(2-4-4) When the rotation angle D of the maximum speed setting dial 69 is (d) the second variable range Dd (D3 or more and less than D4), the correction ratio PA in the second map at this time is the rotation Depending on the value of the angle D, it becomes any value within the range of (VRM ‰ to 1000 ‰). Therefore, the corrected target rotation angle (γmax4) at this time, that is, the maximum rotation angle of the motor 71 is a value shown in the following [Equation 4], and changes according to the value of the rotation angle D.
[Equation 4]
γmax4 = {(γmax−γ2) × VRSH / 1000} + γ2
VRSH = {(1000−VRM) · (D−D3) / (D4−D3)} + VRM

(2-4-5) When the rotation angle D of the maximum speed setting dial 69 is (e) the maximum speed range De (D4 or more and D5 or less), the correction ratio PA in the second map at this time is (1000 ‰). )become. Therefore, the corrected target rotation angle at this time, that is, the maximum rotation angle of the motor 71 becomes the same value as the target rotation angle γmax.

(Operation of rice transplanter)
Hereinafter, the operation of the rice transplanter 1 when the shift pedal 67 is depressed will be described.
It is assumed that the shift pedal 67 of the rice transplanter 1 is depressed in the following order (3-1) to (3-5).
For convenience of explanation, it is assumed that the main transmission lever 65 is operated to the planting position.
In addition, it is assumed that the maximum speed setting dial 69 is operated within (c) a recommended sparse planting speed range Dc (D2 or more and less than D3).

(3-1) As shown in FIG. 9, first, when the shift pedal 67 is not depressed, the rotation angle (pedal rotation angle) α of the shift pedal 67 in this case is expressed as α1 (degrees). To do. In this case, the rotation angle β of the detection shaft of the pedal potentiometer 67a (depression amount β of the transmission pedal 67) is β1 (degrees). When the depression amount β of the shift pedal 67 is not less than β1 and less than β2 (play area), the control device 80 corrects the rotation angle (rotation angle of the motor 71) γ1 (degree) of the detection shaft of the motor potentiometer 71a. The rotation angle is calculated (see (2-1) above). Then, the control device 80 rotates the motor 71 so that the rotation angle γ of the motor 71 becomes the corrected target rotation angle γ1.
When the motor 71 is rotated such that the rotation angle γ of the motor 71 is γ1, the clutch 23 is disconnected via the link mechanism. As a result, the power of the engine 14 is not transmitted to the front wheels 12 and the rear wheels 13, and the vehicle speed V of the rice transplanter 1 becomes 0 (m / sec).
In this case, the braking device 24 is operated via the link mechanism. Thereby, the front wheel 12 and the rear wheel 13 are braked, and the rice transplanter 1 can be prevented from moving forward or backward unexpectedly.
When the motor 71 is rotated such that the rotation angle γ of the motor 71 is γ1, the rotational speed N of the engine 14 is set to N1 (rpm) via the link mechanism.
In this case, the inclination angle of the movable swash plate of the HST 21a is set to be maximum via the link mechanism. Thus, the power from the engine 14 and the power from the HST 21a are combined so as to cancel each other out by the planetary gear mechanism 21b, and the power is not transmitted to the main transmission mechanism 22.

(3-2) When the shift pedal 67 is depressed and the pedal rotation angle α is gradually increased, the depression amount β of the shift pedal 67 is also increased as the pedal rotation angle α is increased.
When the pedal rotation angle α increases from α1 to α2 (less than α2), the depression amount β of the shift pedal 67 increases from β1 to β2 (less than β2) (play area). During this time, the control device 80 sets the correction target rotation angle to γ1 (see (2-1) above), so that the rotation angle γ of the motor 71 remains γ1 regardless of the value of the depression amount β of the shift pedal 67. Holding the motor 71 does not rotate.
When the rotation angle γ of the motor 71 is held at γ1, the clutch 23 is maintained in a disconnected state.
Similarly, when the rotation angle γ of the motor 71 is held at γ1, the braking device 24 is maintained in an activated state.
When the rotation angle γ of the motor 71 is held at γ1, the rotational speed N of the engine 14 is maintained at N1.
Similarly, when the rotation angle γ of the motor 71 is held at γ1, the inclination angle of the movable swash plate of the HST 21a is maintained at the maximum.
Accordingly, even when the shift pedal 67 is depressed and the amount of depression β of the shift pedal 67 increases from β1 to β2 (less than β2), the rotational speed N of the engine 14 remains constant at N1 and The vehicle speed V of the machine 1 is maintained at 0. In this way, an area (so-called “play allowance”) in which the rice transplanter 1 does not travel with respect to the depressing operation of the shift pedal 67 is provided. This is because the rice transplanter 1 is prevented from starting until the shift pedal 67 is depressed a little, thereby preventing the rice transplanter 1 from starting erroneously. Moreover, it is for suppressing the dispersion | variation in the quality by a manufacturing error.

(3-3) When the shift pedal 67 is depressed and the pedal rotation angle α becomes α2, that is, when the depression amount β of the shift pedal 67 becomes β2 (connection region), the control device 80 sets γ2 The correction target rotation angle is calculated (see (2-2) above). Then, the control device 80 rotates the motor 71 so that the rotation angle γ of the motor 71 becomes γ2.
When the motor 71 rotates so that the rotation angle γ of the motor 71 increases from γ1 to γ2, the speed governor 14a of the engine 14 is driven via the link mechanism, and the rotational speed N of the engine 14 is changed from N1 to N2. Increase to.
When the rotation angle γ of the motor 71 becomes γ2 (exceeds γ2), the clutch 23 is connected. As a result, the power of the engine 14 can be transmitted to the front wheels 12 and the rear wheels 13.
Similarly, when the rotation angle γ of the motor 71 becomes γ2, the braking device 24 is released. Thereby, braking of the front wheel 12 and the rear wheel 13 is released, and the rice transplanter 1 can move forward or backward.

(3-4) When the shift pedal 67 is depressed to increase the pedal rotation angle α from α2 to α3, the amount of depression β of the shift pedal 67 increases from β2 to β3 (shift region). At this time, the control device 80 determines the depression amount of the shift pedal 67 from the corrected target rotation angle γ2 (see (2-2) above) corresponding to the rotation angle γ of the motor 71 corresponding to the depression amount β2 of the shift pedal 67. The motor 71 is rotated so as to increase to the corrected target rotation angle γmax3 (see (2-4-3) above) corresponding to β3.
When the motor 71 rotates so that the rotation angle γ of the motor 71 increases from γ2 to γmax3, the speed governor 14a of the engine 14 is driven via the link mechanism, and the rotational speed N of the engine 14 is changed from N1 to Nmax2. Increase to.
Similarly, when the motor 71 rotates so that the rotation angle γ of the motor 71 increases from γ2 to γmax3, the motor 71 is driven to decrease the inclination angle of the movable swash plate of the HST 21a via the link mechanism. As a result, the power of the engine 14 is transmitted to the front wheels 12 and the rear wheels 13 via the HMT 21, and the vehicle speed V of the rice transplanter 1 increases from 0 to the maximum speed Vmax2.

(3-5) When the shift pedal 67 is depressed to the limit and the pedal rotation angle α increases from α3 to αmax, the depression amount β of the shift pedal 67 increases from β3 to βmax (maximum speed holding region). During this time, the control device 80 sets the rotation angle γ of the motor 71 to γmax3 irrespective of the value of the depression amount β of the shift pedal 67 in order to set the corrected target rotation angle to γmax3 (see (2-4-3) above). The motor 71 is not rotated.
Accordingly, the rotational speed N of the engine 14 is maintained at a constant value (Nmax2), and the vehicle speed V (maximum speed) of the rice transplanter 1 is maintained at a constant value (Vmax2). In this way, an area (so-called “margin”) in which the vehicle speed V of the rice transplanter 1 does not increase with respect to the depression operation of the shift pedal 67 is provided. This is to prevent the vehicle speed from reacting sensitively so that the vehicle speed is not changed as long as the amount of depression of the speed change pedal is slightly changed due to the road surface condition or the like. Moreover, it is for suppressing the dispersion | variation in the quality by a manufacturing error.
As described above, when the rotation angle of the maximum speed setting dial 69 is (c) the recommended sparse planting speed range Dc (D2 or more and less than D3), the maximum speed of the rice transplanter 1 becomes a constant value (Vmax2).

As described above, the rice transplanter 1 according to the present embodiment can increase (accelerate) the vehicle speed V of the rice transplanter 1 by depressing the shift pedal 67. Contrary to the above description, the vehicle speed V of the rice transplanter 1 can be reduced (decelerated) by returning the stepped-on shift pedal 67 to the original position.

As shown in (3-3) to (3-5) above, regarding the operation of the rice transplanter 1, the maximum speed setting dial 69 is operated within the (c) sparse planting recommended speed range Dc (D2 or more and less than D3). In this case, when the shift pedal 67 is depressed from β2 to βmax, the rotation angle γ of the motor 71, the rotational speed N of the engine 14, and the vehicle speed V of the rice transplanter 1 change as shown by the solid line in FIG. To do.
In this case, when the shift pedal 67 is depressed to the limit (βmax), the rotation angle γ of the motor 71 becomes γmax3 (see (2-4-3) above).
Then, the rotational speed N of the engine 14 becomes Nmax2 corresponding to the corrected target rotational angle γmax3. Then, the vehicle speed V (maximum speed) of the rice transplanter 1 becomes Vmax2 corresponding to the rotational speed Nmax2 of the engine 14.

Regarding the operation of the rice transplanter 1, when the maximum speed setting dial 69 is operated within (a) the minimum speed range Da (D0 or more and less than D1), when the shift pedal 67 is depressed from β2 to βmax, The rotation angle γ of the motor 71, the rotational speed N of the engine 14, and the vehicle speed V of the rice transplanter 1 change as shown by a one-dot chain line in FIG.
In this case, when the shift pedal 67 is depressed to the limit (βmax), the rotation angle γ of the motor 71 becomes γmax1 (see (2-4-1) above).
Then, the rotational speed N of the engine 14 becomes Nmax1 corresponding to the corrected target rotation angle γmax1. Then, the vehicle speed V (maximum speed) of the rice transplanter 1 becomes Vmax1 corresponding to the rotational speed Nmax1 of the engine 14.

Regarding the operation of the rice transplanter 1, when the maximum speed setting dial 69 is operated within (e) the maximum speed range De (D4 or more and D5 or less), the depression amount β of the shift pedal 67 is from β2 to βmax. When increasing, the rotation angle γ of the motor 71, the rotational speed N of the engine 14, and the vehicle speed V of the rice transplanter 1 change as shown by the two-dot chain line in FIG.
In this case, when the shift pedal 67 is depressed to the limit (βmax), the rotation angle γ of the motor 71 becomes γmax (see (2-4-5) above).
Then, the rotational speed N of the engine 14 becomes Nmax3 corresponding to the corrected target rotational angle γmax. The vehicle speed V (maximum speed) of the rice transplanter 1 becomes Vmax3 corresponding to the rotational speed Nmax3 of the engine 14.

Regarding the operation of the rice transplanter 1, when the maximum speed setting dial 69 is operated within (b) the first variable range Db (D1 or more and less than D2), the speed change is performed as shown in (3-5) above. When the pedal 67 is depressed to the limit, the corrected target rotation angle γmax2 changes corresponding to the value of the rotation angle D of the maximum speed setting dial 69 (see (2-4-2) above).
Then, the rotational speed N of the engine 14 is changed in accordance with the value of the rotational angle D (corrected target rotational angle γmax2) of the maximum speed setting dial 69, whereby the maximum speed of the rice transplanter 1 is changed to the rotational speed of the engine 14. It is changed corresponding to the change of N. In this case, the rotational speed N of the engine 14 is changed in the range of Nmax1 to Nmax2, and the maximum speed of the rice transplanter 1 is changed in the range of Vmax1 to Vmax2.
That is, when the rotation speed of the maximum speed setting dial 69 is (b) the first variable range Db (D1 or more and less than D2), the maximum speed of the rice transplanter 1 corresponds to the rotation angle value of the maximum speed setting dial 69. Thus, it is changed in the range of Vmax1 to Vmax2.

Regarding the operation of the rice transplanter 1, when the maximum speed setting dial 69 is operated within (d) the second variable range Dd (D3 or more and less than D4), the speed change is performed as shown in (3-5) above. When the pedal 67 is depressed to the limit and the depression amount β of the shift pedal 67 increases from β3 to βmax, the corrected target rotation angle γmax4 changes corresponding to the value of the rotation angle D of the maximum speed setting dial 69. (Refer to (2-4-4) above).
Then, the rotational speed N of the engine 14 is changed in accordance with the value of the rotational angle D (corrected target rotational angle γmax4) of the maximum speed setting dial 69, whereby the maximum speed of the rice transplanter 1 is changed to the rotational speed of the engine 14. It is changed corresponding to the change of N. In this case, the rotational speed N of the engine 14 is changed in the range of Nmax2 to Nmax3, and the maximum speed of the rice transplanter 1 is changed in the range of Vmax2 to Vmax3.
That is, when the rotation speed of the maximum speed setting dial 69 is (d) the second variable range Dd (D3 or more and less than D4), the maximum speed of the rice transplanter 1 corresponds to the rotation angle value of the maximum speed setting dial 69. Thus, it is changed within the range of Vmax2 to Vmax3.

The magnitude relationship between the engine speeds Nmax1 to Nmax3 is configured such that Nmax1 <Nmax2 <Nmax3.

(Vehicle speed fixed by speed fixing lever)
Below, the procedure at the time of the vehicle speed fixation of the rice transplanter 1 being cancelled | released by the speed fixing lever 70 is demonstrated.

When the speed fixing lever 70 is switched to the fixed position while the rice transplanter 1 is traveling, the vehicle speed at this time is fixed (maintained).
In the present embodiment, it is assumed that the operator has fixed the vehicle speed of the rice transplanter 1 with the speed fixing lever 70 when the depression amount β of the speed change pedal 67 reaches the fixed storage position βx. At this time, the rotation angle γ of the motor potentiometer 71a (the rotation angle γ of the motor 71) is the fixed rotation angle γx, and the vehicle speed of the rice transplanter 1 is the fixed vehicle speed Vx3.
When the speed fixing lever 70 is in the fixed position, the control device 80 switches the rotation angle γ of the motor 71 to a fixed value, more specifically, the speed fixing lever 70 is switched to the fixed position regardless of the depression amount β of the speed change pedal 67. The value at the time (fixed rotation angle γx) is maintained. Thereby, irrespective of the depression amount β of the shift pedal 67, the vehicle speed of the rice transplanter 1 is fixed to the fixed vehicle speed Vx3, and the rice transplanter 1 continues to travel at the fixed vehicle speed Vx3.
In addition, the control device 80 stores information related to the fixed storage position βx of the shift pedal 67 and information related to the fixed rotation angle γx of the motor 71.

When the speed fixing lever 70 is switched to the release position with the vehicle speed of the rice transplanter 1 fixed at the fixed vehicle speed Vx3, that is, when the control device 80 acquires the release signal from the speed fixation release switch 70b, The device 80 releases the vehicle speed fixed by the speed fixing lever 70.
When the speed fixing lever 70 is in the release position, the control device 80 changes the vehicle speed V of the rice transplanter 1 to a magnitude corresponding to the depression amount β of the shift pedal 67 (see FIG. 9).

(Adjustment of fixed vehicle speed using the maximum speed setting dial)
In the following, when the vehicle speed V of the rice transplanter 1 is fixed to the fixed vehicle speed Vx3 by the speed fixing lever 70, the fixed vehicle speed Vx3 is finely adjusted by the maximum speed setting dial 69 in a state where the speed fixing lever 70 is in the fixed position. The configuration for enabling the change will be described. It is assumed that the maximum speed setting dial 69 is rotated to the maximum speed range De (D4 or more and D5 or less) in a state where the speed fixing lever 70 is at the fixed position.

When the vehicle speed V of the rice transplanter 1 is fixed to the fixed vehicle speed Vx3 (rotation angle of the motor 71: fixed rotation angle γx) by the speed fixing lever 70, the control device 80 rotates the rotation speed of the maximum speed setting dial 69. The adjustment target rotation angle is calculated by changing (adjusting) the fixed rotation angle γx of the motor 71 based on (the dial signal), and the motor 71 is rotated so that the calculated adjustment target rotation angle is obtained. By moving, the fixed vehicle speed Vx3 of the rice transplanter 1 is changed (finely adjusted).
Specifically, the fixed vehicle speed Vx3 is finely adjusted by the following procedures (4-1) to (4-2).
(4-1) When the rotation angle of the motor 71 is maintained at the fixed rotation angle γx by the speed fixing lever 70, and the vehicle speed V of the rice transplanter 1 is fixed to the fixed vehicle speed Vx3, the control device 80 Then, a third map showing the correspondence between the rotation angle D of the maximum speed setting dial 69 and the correction ratio PB (adjustment target rotation angle) of the fixed rotation angle γx of the motor 71 is created.
FIG. 10 shows the third map. 10, the horizontal axis indicates the rotation angle D of the maximum speed setting dial 69, and the vertical axis indicates the correction ratio PB of the fixed rotation angle γx of the motor 71.
As shown in FIG. 9, the horizontal axis of the third map has the same configuration as the horizontal axis of the second map shown in FIG. 8, and a detailed description thereof will be omitted.
The vertical axis of the third map indicates the correction ratio PB of the fixed rotation angle γx of the motor 71. The correction ratio PB indicates the ratio when the fixed rotation angle γx is corrected (corrected) according to the rotation angle D of the maximum speed setting dial 69 in terms of thousandths.
In the lowest speed range Da (D0 or more and less than D1) in the third map, the correction ratio PB is held at a constant value (VRS ‰).
In the first variable range Db (D1 or more and less than D2) in the third map, the correction ratio PB is (VRSM = {(VRM−VRS) · (D−D1) / (D2−D1)} + VRS ‰). As the rotation angle D of the maximum speed setting dial 69 increases, the rotation speed increases from (VRS ‰) corresponding to the rotation angle D1 to (VRM ‰) corresponding to the rotation angle D2.
In the sparse vegetation recommended speed range Dc (D2 or more and less than D3) in the third map, the correction ratio PB is held at a constant value (VRM ‰).
In the second variable range Dd (D3 or more and less than D4) in the third map, the correction ratio PB is (VRSH = {(1000−VRM) · (D−D3) / (D4−D3)} + VRM ‰). As the rotational angle D of the maximum speed setting dial 69 increases, the rotational speed increases from (VRM ‰) corresponding to the rotational angle D3 to (1000 ‰) corresponding to the rotational angle D4.
In the maximum speed range De (D4 or more and D5 or less) in the third map, the correction ratio PB is held at a constant value (1000 ‰).

(4-2) The control device 80 determines the fixed rotation angle γx of the motor 71 based on the dial signal (the rotation angle D of the highest speed setting dial 69) acquired from the highest speed setting dial 69. The adjustment target rotation angle is calculated by adjusting (changing) the moving angle γx. Then, the control device 80 changes (finely adjusts) the fixed vehicle speed Vx3 by rotating the motor 71 so that the calculated adjustment target rotation angle is obtained.
In the present embodiment, the adjustment target rotation angle is calculated using the third map, and according to the rotation angle D of the maximum speed setting dial 69, the following (4-2-1) to (4- 4-2-5).
(4-2-1) When the rotation angle D of the maximum speed setting dial 69 is (a) the minimum speed range Da (D0 or more and less than D1), the adjustment target rotation angle (γx1) at this time is In the three maps, calculation is performed using a value (VRS ‰) corresponding to the minimum speed range Da.
The adjustment target rotation angle (γx1) is a constant value (γx · VRS / 1000).
(4-2-2) When the rotation angle D of the maximum speed setting dial 69 is (b) the first variable range Db (D1 or more and less than D2), the adjustment target rotation angle (γx2) at this time is In the third map, calculation is performed using a value (VRSM ‰) corresponding to the first variable range Db.
The adjustment target rotation angle (γx2) is (γx · VRSM / 1000), and changes according to the value of the rotation angle D.
(4-2-3) When the rotation angle D of the maximum speed setting dial 69 is (c) the sparse planting recommended speed range Dc (D2 or more and less than D3), the adjustment target rotation angle (γx3) at this time is In the third map, calculation is performed using a value (VRM ‰) corresponding to the recommended sparse planting speed range Dc.
The adjustment target rotation angle (γx3) is a constant value (γx3 = γx · VRM / 1000).
(4-2-4) When the rotation angle D of the maximum speed setting dial 69 is (d) the second variable range Dd (D3 or more and less than D4), the adjustment target rotation angle (γx4) at this time is In the third map, calculation is performed using a value (VRSH ‰) corresponding to the second variable range Dd.
The adjustment target rotation angle (γx4) is (γx · VRSH / 1000), and changes according to the value of the rotation angle D.
(4-2-5) When the rotation angle D of the maximum speed setting dial 69 is (e) the maximum speed range De (D4 or more and D5 or less), the adjustment target rotation angle (γx5) at this time is In the three maps, calculation is performed using a value (1000 ‰) corresponding to the maximum speed range De.
The adjustment target rotation angle (γx5) is a constant value (γx5 = γx · 1000/1000 = γx), and the adjustment target rotation angle and the fixed rotation angle are the same value γx.

Accordingly, when the maximum speed setting dial 69 is rotated from (e) the maximum speed range De (D4 to D5) to (a) the minimum speed range Da (D0 to less than D1), (e) the maximum speed range In De (D4 or more and D5 or less), the adjustment target rotation angle becomes a constant value (γx5 = γx). Thereby, the vehicle speed of the rice transplanter 1 remains unchanged at the fixed vehicle speed Vx3.
In the same case, (d) in the second variable range Dd (D3 or more and less than D4), the adjustment target rotation angle (γx4) corresponds to the rotation angle D4 of the maximum speed setting dial 69 (γx5 = γx). , It decreases to (γx3) corresponding to the rotation angle D3. Thereby, the vehicle speed of the rice transplanter 1 decreases from the fixed vehicle speed Vx3 corresponding to the adjustment target rotation angle (γx5 = γx) to (Vx2) corresponding to the adjustment target rotation angle (γx3).
In the same case, in (c) the recommended sparse planting speed range Dc (D2 or more and less than D3), the adjustment target rotation angle becomes a constant value (γx3). Thereby, the vehicle speed of the rice transplanter 1 remains unchanged (Vx2) corresponding to the adjustment target rotation angle (γx3).
In the same case, (b) In the first variable range Db (D1 or more and less than D2), the adjustment target rotation angle (γx2) is rotated from (γx3) corresponding to the rotation angle D2 of the maximum speed setting dial 69. It decreases to (γx1) corresponding to the moving angle D1. As a result, the vehicle speed of the rice transplanter 1 decreases from (Vx2) corresponding to the adjustment target rotation angle (γx3) to (Vx1) corresponding to the adjustment target rotation angle (γx1).
In the same case, (a) In the minimum speed range Da (D0 or more and less than D1), the adjustment target rotation angle becomes a constant value (γx1). Thereby, the vehicle speed of the rice transplanter 1 remains unchanged (Vx1) corresponding to the adjustment target rotation angle (γx1).

As described above, the rice transplanter 1 can fix the fixed vehicle speed by rotating the maximum speed setting dial 69 while the speed fixing lever 70 is in the fixed position after the vehicle speed V is fixed to Vx3 by the speed fixing lever 70. Vx3 can be changed (adjusted).
When calculating the adjustment target turning angle, the control device 80 turns the motor 71 when the speed fixing lever 70 starts fixing the vehicle speed and the maximum speed setting dial 69 when the speed fixing lever 70 starts fixing the vehicle speed. And (rotation angle of the motor 71 when the vehicle speed is fixed by the speed fixing lever 70) × (current maximum speed setting). The rotation angle D of the dial 69) / (the rotation angle D of the maximum speed setting dial 69 when the speed fixing lever 70 starts to fix the speed) may be used.

It should be noted that the correction ratios PB (VRS ‰), (VRSM ‰), (VRM ‰), and (VRSH ‰) in the third map are the correction ratios PA (VRS ‰), (VRSM ‰) in the second map, (VRM ‰) and (VRSH ‰) are configured with the same values.
Thereby, in the rice transplanter 1, the operation feeling when the maximum speed of the rice transplanter 1 is set by the turning operation of the maximum speed setting dial 69 and the fixed vehicle speed is adjusted by the turning operation of the maximum speed setting dial 69. The operation feeling at the time is configured to approximate.
In addition, the dashed-two dotted line of FIG. 8 has shown the state when said 3rd map is represented on said 2nd map.

In this embodiment, the motor 71 is configured to change the rotational speed of the engine 14 and the gear ratio of the HST 21a. However, the present invention is not limited to this, and the motor 71 changes the rotational speed of the engine 14 or the gear ratio of the HST 21a. You may comprise. Further, when the motor 71 is configured to change the rotational speed of the engine 14 and the gear ratio of the HST 21a, the motor 71 may be configured by one motor, or the first motor that changes the rotational speed of the engine 14 and You may comprise with the 2nd motor which changes the gear ratio of HST21a.

(Release the vehicle speed)
In the following, when the vehicle speed V of the rice transplanter 1 is fixed to Vx3 by the speed fixing lever 70, the vehicle speed fixing is released by an operation other than the switching operation of the speed fixing lever 70 or the depression of the brake pedal 68 ( i) to (ii) will be described.

(I) A configuration in which the release of the fixed vehicle speed is performed by turning the maximum speed setting dial 69 will be described.
When the vehicle speed V is fixed to Vx3 by operating the speed fixing lever 70, the control device 80 sets a predetermined dial lower limit threshold value VRX (VRS <VRX <VRM) for the correction ratio PB in the third map. To do.
As shown in FIG. 10, the release of the vehicle speed is fixed when the maximum speed setting dial 69 is rotated and the rotation angle D of the maximum speed setting dial 69 is decreased. This is performed when the correction ratio PB corresponding to the moving angle D becomes a value less than the dial lower limit threshold VRX.
That is, when the maximum speed setting dial 69 is turned and the fixed vehicle speed Vx3 is changed to the low speed side, the changed vehicle speed corresponds to the dial lower limit threshold value VRX. This is performed when the vehicle speed is less than the lower speed threshold (Vx0) (see FIG. 10). When the release of the fixed vehicle speed is performed, the rice transplanter 1 returns to a state in which the vehicle speed can be controlled by the depression operation of the shift pedal 67. The speed lower limit threshold (dial lower limit threshold) is a value that is appropriately determined by experiments or the like. Further, for example, the control device 80 determines whether or not the vehicle speed has become a value less than the speed lower limit threshold based on the rotation angle of the motor 71.
With this configuration, when the vehicle speed is fixed by the speed fixing lever 70 in the low speed range and the maximum speed setting dial 69 is rotated to the low speed side (the vehicle speed decreases side), the motor 71 It is possible to prevent the vehicle speed fixed state by the speed fixing lever 70 from being maintained in a state where the adjustment target rotation angle is γ2 or less and the rice transplanter 1 is stopped traveling.

(Ii) Two configurations will be described in which the release of the fixed vehicle speed is performed by depressing the shift pedal 67.
(First configuration)
As described above, the control device 80 stores information related to the fixed storage position βx of the shift pedal 67 corresponding to the fixed vehicle speed Vx3.
When the vehicle speed V is fixed at Vx3 by the operation of the speed fixing lever 70, the control device 80 sets the fixed release lower limit βx1 in the third map. As shown in FIG. 11A, the fixed release lower limit value βx1 is larger than the depression amount β1 of the shift pedal 67 when the depression operation of the shift pedal 67 is released, and the fixed storage position βx corresponding to the fixed vehicle speed Vx3. The value is smaller than (β1 <βx1 <βx), and is a value determined as appropriate by experiments or the like.
As shown in FIG. 11A, the release of the vehicle speed fixed by the operation of depressing the shift pedal 67 is performed when the depressing amount β of the shift pedal 67 is the fixed release lower limit βx1 in a state where the speed fixing lever 70 is in the fixed position. This is performed when the value decreases to less than (β1 <βx1 <βx) and then increases to the fixed release lower limit βx1.
When configured in this manner, the vehicle speed V of the rice transplanter 1 becomes slower than the fixed vehicle speed Vx3 when the vehicle speed fixation is released.
(Second configuration)
When the vehicle speed V is fixed to Vx3 by the operation of the speed fixing lever 70, the control device 80 sets the fixed release upper limit βx2 in the third map. As shown in FIG. 11B, the fixed release upper limit βx2 is a value (βx <βx2) larger than the fixed storage position βx corresponding to the fixed vehicle speed Vx3, and is a value that is appropriately determined by experiments or the like.
As shown in FIG. 11B, the release of the vehicle speed fixed by the operation of depressing the shift pedal 67 is performed when the depressing amount β of the shift pedal 67 is the fixed release upper limit βx2 ( Performed when βx <βx2).
When configured in this manner, the vehicle speed V of the rice transplanter 1 becomes faster than the fixed vehicle speed Vx3 when the vehicle speed fixation is released.
The vehicle speed fixed release according to the first configuration is such that the depression amount β of the speed change pedal 67 decreases to less than the fixed release lower limit value βx1 in a state where the depression amount β is less than the fixed release upper limit value βx2, and the fixed release lower limit value βx1 (See FIG. 11A).
On the other hand, the release of the vehicle speed fixation by the second configuration is performed when the depression amount β of the speed change pedal 67 increases to the fixation release upper limit value βx2 in a state of being equal to or larger than the fixation release lower limit value βx1 ( (Refer FIG.11 (b)).
Accordingly, by appropriately adjusting the depression amount of the shift pedal 67, when the vehicle speed fixed is released by the depression operation of the shift pedal 67, the vehicle speed V of the rice transplanter 1 is made slower than the fixed vehicle speed Vx3 (the first vehicle described above) It is possible to select whether to speed up (see the second configuration).

Regarding (ii) above, when the fixed vehicle speed Vx3 is adjusted (changed) by rotating the maximum speed setting dial 69 while the vehicle speed V is fixed to Vx3 by the operation of the speed fixing lever 70, the maximum speed The fixed release lower limit βx1 and the fixed release upper limit βx2 may be changed according to the rotation angle of the setting dial 69.
Specifically, when the maximum speed setting dial 69 is turned to the high speed side (the vehicle speed increases), the control device 80 increases the fixed release lower limit value βx1 and the fixed release upper limit value βx2g to larger values. change.
Further, when the maximum speed setting dial 69 is rotated to the low speed side (the vehicle speed decreases), the control device 80 changes the fixed release lower limit value βx1 and the fixed release upper limit value βx2g to smaller values. .
With this configuration, it is possible to prevent the rice transplanter 1 from suddenly accelerating or decelerating when the vehicle speed is released by depressing the shift pedal 67 as shown in (ii) above.

As described above, the rice transplanter 1
A motor 71 that changes the rotational speed of the engine 14 and / or the gear ratio of the HST 21a;
A shift pedal 67 which is an operating tool for changing the rotation angle of the motor 71;
A control device 80 that is connected to the motor 71 and the speed change pedal 67, and that changes at least one of the rotational speed of the engine 14 and the speed ratio of the HST 21a by the motor 71 based on the depression amount of the speed change pedal 67 to change the vehicle speed; ,
A maximum speed setting dial 69 that is connected to the control device 80 and is an operating tool for changing the maximum speed that is the vehicle speed when the shift pedal 67 is depressed to the limit;
The control device 80
The target rotation angle of the motor 71 is calculated based on the depression amount of the shift pedal 67, and the motor 71 is rotated so that the rotation angle of the motor 71 becomes the target rotation angle. Change the size to correspond to the target rotation angle of
By changing the target rotation angle of the motor 71 when the shift pedal 67 is depressed to the limit to a size corresponding to the rotation angle of the maximum speed setting dial 69, the maximum speed is set to the maximum speed setting dial 69. Change the size to correspond to the rotation angle.

From this, if you set the vehicle speed (maximum speed) with the maximum speed setting dial 69 according to the scene, such as moving, working, loading and unloading from the truck, barn, etc., you can depress the shift pedal 67 with full stroke (depress to the limit) The rice transplanter 1 can be driven at a desired vehicle speed. Therefore, a very small amount of operation of the shift pedal 67 is not required, and it is possible to easily implement the rice transplanter 1 at a desired vehicle speed.
In addition, even if the operator's posture is unstable, such as entering or leaving the field or loading / unloading from a truck, even if the operator performs an incorrect operation, the speed is changed only up to the maximum speed set by the maximum speed setting dial 69, so that it is stable. It is advantageous in terms of sex.

In the rice transplanter 1,
The maximum speed setting dial 69 can be rotated, and within the rotation range, the variable range for changing the maximum speed corresponding to the amount of change in the rotation angle, and the change in the rotation angle. A constant speed region that maintains the maximum speed at a constant value.

Thus, when the maximum speed setting dial 69 is rotated to set the maximum speed, the maximum speed is a constant value corresponding to the constant speed range if the maximum speed setting dial 69 is rotated within the constant speed range. Therefore, it is possible to easily set the maximum speed.

In the rice transplanter 1,
The constant speed range has a minimum speed range, a maximum speed range, and a sparse recommended speed range provided between the minimum speed range and the maximum speed range,
The variable range includes a first variable range provided between the minimum speed range and the recommended sparse planting speed range, and a second variable range provided between the recommended sparse planting speed range and the maximum speed.

Accordingly, when the maximum speed setting dial 69 is rotated to set the maximum speed, the maximum speed Vmax1 corresponding to the minimum speed range, the maximum speed Vmax2 corresponding to the recommended sparse planting speed range, and the maximum speed range It is possible to easily set the maximum speed Vmax3 corresponding to.
In addition, since the maximum speed of the rice transplanter 1 can be easily set to the maximum speed Vmax2 that is optimal for sparse planting work, it is possible to improve planting accuracy when performing sparse planting work.
Further, by providing a recommended vehicle speed setting area such as sparse planting, it is possible to prevent the planting rotor from being crushed.

In the rice transplanter 1,
A motor 71 that changes the rotational speed of the engine 14 and / or the gear ratio of the HST 21a;
A shift pedal 67 which is an operating tool for changing the rotation angle of the motor 71;
A control device 80 that is connected to the motor 71 and the speed change pedal 67, and that changes at least one of the rotational speed of the engine 14 and the speed ratio of the HST 21a by the motor 71 based on the depression amount of the speed change pedal 67 to change the vehicle speed; ,
A maximum speed setting dial 69 that is connected to the control device 80 and is an operating tool for changing the maximum speed that is the vehicle speed when the shift pedal 67 is depressed to the limit;
A speed fixing lever 70 which is connected to the control device 80 and is an operating tool for fixing the vehicle speed to a constant value regardless of the depression operation of the shift pedal 67;
The control device 80 is used when the vehicle speed is fixed by the speed fixing lever 70, that is, when the speed fixing lever 70 is at the fixed position and the motor 71 does not rotate by the depression operation of the shift pedal 67. When the high speed setting dial 69 is rotated, the rotation angle of the motor 71 is changed based on the rotation angle of the maximum speed setting dial 69, thereby fixing the vehicle speed (fixed vehicle speed Vx3) by the speed fixing lever 70. ) Is changed to a size corresponding to the rotation angle of the maximum speed setting dial 69.

From this, if you set the vehicle speed (maximum speed) with the maximum speed setting dial 69 according to the scene, such as moving, working, loading and unloading from the truck, barn, etc., you can depress the shift pedal 67 with full stroke (depress to the limit) The rice transplanter 1 can be driven at a desired vehicle speed. Therefore, a very small amount of operation of the shift pedal 67 is not required, and it is possible to easily implement the rice transplanter 1 at a desired vehicle speed.
Further, the vehicle speed fixed by the speed fixing lever 70 can be increased or decreased by rotating the maximum speed setting dial 69 while the speed fixing lever 70 is at the fixed position. Accordingly, the vehicle speed fixed by the speed fixing lever 70 can be adjusted smoothly.
Conventionally, when the vehicle speed of the rice transplanter is fixed to a constant value (fixed vehicle speed) by the speed fixing means, when the operator changes the fixed vehicle speed, the operator temporarily releases the vehicle speed fixed by the speed fixing means, Then, after the vehicle speed of the rice transplanter has been adjusted to increase or decrease to a desired vehicle speed by depressing the shift pedal, the vehicle speed must be fixed again by the speed fixing means. This requires complicated work.
On the other hand, the rice transplanter 1 can change the fixed vehicle speed Vx3 only by rotating the maximum speed setting dial 69. Therefore, the increase / decrease adjustment of the fixed vehicle speed Vx3 can be performed smoothly.

In the rice transplanter 1,
When the vehicle speed is fixed by the speed fixing lever 70 and the vehicle speed after the change by the maximum speed setting dial 69 is less than the predetermined speed lower limit threshold Vx0, the control device 80 uses the speed fixing lever 70. Release the vehicle speed lock.

As a result, the vehicle speed is fixed by the speed fixing lever 70 in the low speed range, and the target rotation angle of the motor 71 is adjusted when the maximum speed setting dial 69 is rotated to the low speed side (the vehicle speed decreases). Becomes γ2 or less, and it is possible to prevent the vehicle speed fixed state by the speed fixing lever 70 from being maintained while the rice transplanter 1 has stopped traveling.

In the rice transplanter 1,
The control device 80
When the vehicle speed is fixed by the speed fixing lever 70, when the amount of depression of the speed change pedal 67 decreases to less than a predetermined fixed release lower limit value βx1, and then increases to the fixed release lower limit value βx1, Release the vehicle speed fixed by the fixing lever 70,
When the vehicle speed is fixed by the speed fixing lever 70 and the amount of depression of the shift pedal 67 increases to the predetermined fixing release upper limit βx2, the vehicle speed fixing by the speed fixing lever 70 is released,
The unlocking lower limit βx1 is a value smaller than the fixed storage position βx, which is the depression amount of the shift pedal 67 when the speed fixing lever 70 is operated and the vehicle speed is fixed.
The fixed release upper limit βx2 is a value larger than the fixed storage position βx.

This allows the operator to select whether to slow down or speed up the vehicle speed when the vehicle speed is released by depressing the shift pedal 67.

In the rice transplanter 1,
In the case where the vehicle speed is fixed by the speed fixing lever 70 and the maximum speed setting dial 69 is rotated, the control device 80 determines the fixed release lower limit βx1 according to the rotation angle of the maximum speed setting dial 69. , And the fixed release upper limit βx2.

This makes it possible to prevent the rice transplanter 1 from suddenly accelerating or decelerating when the fixed vehicle speed is released by depressing the shift pedal 67.

Hereinafter, a rice transplanter that has good operability and can appropriately change the engine speed and the gear ratio of the continuously variable transmission according to the driving situation and working situation will be described.

Conventionally, a rice transplanter having a configuration in which power from an engine is shifted by a continuously variable transmission and transmitted to a traveling unit and a planting unit is known. In such a rice transplanter, after operating the accelerator lever and setting the engine speed, operating the shift pedal to change the gear ratio of the continuously variable transmission, the travel speed (work speed during work) It is set as the structure which changes.

The conventional rice transplanter has a configuration in which an operator operates the accelerator lever and the shift pedal separately to change the engine speed and the transmission gear ratio of the continuously variable transmission. It was. Further, the speed of the engine and the speed of the continuously variable transmission can be changed according to the traveling situation of the rice transplanter (for example, the situation of entering and exiting the field) and the working situation (for example, the situation of planting work in mud). There was also a problem that the ratio could not be changed appropriately.

Therefore, there is provided a rice transplanter that has good operability and can appropriately change the engine speed and the transmission gear ratio of the continuously variable transmission according to the driving situation and working situation.

The rice transplanter includes an engine, a first actuator that changes a rotational speed of the engine, a continuously variable transmission that changes power from the engine, a second actuator that changes a transmission ratio of the continuously variable transmission, The first actuator and the second actuator are controlled based on a detected value of the speed change operation tool, an operation amount detection means for detecting an operation amount of the speed change operation tool, and an operation amount detection means. A control device.

Thereby, the rice transplanter can change the traveling speed and work speed of the rice transplanter by controlling the first actuator and the second actuator based on the detection value of the operation amount detection means. Therefore, the operator can change the traveling speed and work speed of the rice transplanter with only the speed change operation tool, and the operability is improved. Further, the engine speed and the gear ratio of the continuously variable transmission can be appropriately changed in accordance with the traveling situation and work situation of the rice transplanter.

In the rice transplanter, the control device includes a map related to the fuel efficiency of the engine, a map related to the gear shift efficiency of the continuously variable transmission, a map related to the exhaust gas emission rate of the engine, and a load factor of the engine. At least one of the maps is stored, and the control device controls the first actuator and the second actuator based on the stored map and the detection value of the operation amount detection means.

Thereby, the control device can improve the fuel efficiency by controlling the first actuator and the second actuator based on the map related to the fuel efficiency. Further, by controlling the first actuator and the second actuator based on the map related to the shift efficiency, the shift efficiency can be improved in the entire speed range. Further, the exhaust gas can be reduced by controlling the first actuator and the second actuator based on the map related to the exhaust gas emission rate. Further, by controlling the first actuator and the second actuator based on the map relating to the load factor of the engine, it is possible to travel reliably even when the engine is overloaded due to inclination or the like.

In the rice transplanter, power is transmitted from the engine to the PTO output shaft.

This allows the rice transplanter to change the rotational speed of the PTO output shaft by changing the rotational speed of the engine. Therefore, the speed increasing / decreasing gear and the speed change mechanism are not required, and the cost can be reduced.

Hereinafter, the overall configuration of the rice transplanter 200 will be described. In addition, although the rice transplanter 200 is an eight-planted rice transplanter, this is not particularly limited, and for example, a six-row or ten-row planter may be used.

As shown in FIG. 12, the rice transplanter 200 has a traveling unit 210 and a planting unit 240, and is configured so that seedlings can be planted in the field by the planting unit 240 while traveling by the traveling unit 210. The The planting unit 240 is disposed behind the traveling unit 210 and is connected to the rear portion of the traveling unit 210 via an elevating mechanism 230 so as to be movable up and down.

The elevating mechanism 230 is provided between the traveling unit 210 and the planting unit 240. Specifically, the top link 231 and the lower link 232 are installed between the traveling unit 210 and the planting unit 240, and the lifting cylinder is connected between the lower link 232 and the traveling unit 210. The planting part 240 can be rotated in the vertical direction with respect to the traveling part 210, that is, can be raised and lowered by the expansion and contraction operation of the lifting cylinder.

In the traveling unit 210, the engine 214 is provided at the front portion of the vehicle body frame 211 and is covered with a bonnet 215. The mission case 100 is supported by the front portion of the vehicle body frame 211 and is disposed behind the engine 214. The front axle case 216 is supported on the front portion of the vehicle body frame 211, and the front wheels 212 are attached to the left and right sides of the front axle case 216. The rear axle case 217 is supported on the rear portion of the vehicle body frame 211, and the rear wheels 213 are attached to the left and right sides of the rear axle case 217.

In the traveling unit 210, a driving operation unit 220 is provided in the middle of the vehicle body 211 in the front and rear direction. A dashboard 221 is disposed at the front of the driving operation unit 220, a steering handle 224 is disposed at the left and right center of the dashboard 221, and a driver seat 222 is disposed behind the steering handle 224. Below the driver's seat 222, a vehicle body cover 223, a part of which is a step for getting on and off, is disposed. In the driving operation unit 220, a plurality of operation tools including a main transmission lever 225 and a transmission pedal 226 are arranged, and it is possible to perform appropriate operations on the traveling unit 210 and the planting unit 240 with these operation tools. It is said.

In the planting part 240, the planting mission case 247 is supported near the lower center of the planting frame 249, and the transmission shaft extends from the planting mission case 247 to the left and right sides. Four planting transmission cases 246 are respectively extended rearward from the transmission shaft, and are arranged at appropriate intervals in the left-right direction.

The rotary case 244 is rotatably supported on the left and right sides of the rear end of each planting transmission case 246. The number of rotary cases 244 is the same as the number of planting strips, that is, eight. The two planting claws 245 are attached to both sides of the rotary case 244 in the longitudinal direction so as to sandwich the rotation fulcrum of the rotary case 244.

The seedling mounting table 241 is arranged above the planting transmission case 246 in an inclined state with a front height and a low height. The seedling mount 241 is attached to the rear portion of the planting frame 249 through a guide rail so as to be capable of reciprocating in the left-right direction. The seedling table 241 can be reciprocated horizontally by a lateral feed mechanism.

The seedling mounting bases 241 provided with a plurality of (8) seedling mat mounting parts are arranged in the left-right direction so that the lower ends of the seedling mounting bases 241 face one rotary case 244. Then, the seedling mat is placed on each seedling mounting table 241, and one seedling can be cut from the seedling mat on the seedling mounting table 241 by the planting claws 245 when the rotary case 244 rotates.

In the planting unit 240, a plurality of floats 242 that level the farm scene and a leveling rotor 243 that leveles the rough headland after turning are supported by the planting frame 249 so as to be movable up and down. Yes. In addition, left and right drawing markers 248 for drawing on the field are rotatably supported on the left and right sides of the planting frame 249.

Hereinafter, the power transmission structure inside the mission case 100 will be described with reference to FIG.

The power of the engine 214 is transmitted to the front wheel 212, the rear wheel 213, and the planting part 240 via a power transmission mechanism provided inside the mission case 100. Inside the mission case 100, a hydraulic-mechanical continuously variable transmission (HMT) 110, a main clutch 130, a main transmission mechanism 140, and a braking device 150 are mounted.

The engine 214 is configured to be able to increase or decrease the power (the number of revolutions) by adjusting the fuel injection amount by the speed governor 214a. The power of the engine 214 is transmitted to the input shaft 101 of the mission case 100 via a V-belt or a propeller shaft.

The HMT 110 is a continuously variable transmission, and includes a variable displacement hydraulic pump 111, a fixed displacement hydraulic motor 112, and a planetary gear mechanism 120. The motive power input from the input shaft 101 of the mission case 100 drives the hydraulic pump 111 and feeds the hydraulic oil from the hydraulic pump 111 to the hydraulic motor 112 to rotate the motor shaft 113 of the hydraulic motor 112.

The movable swash plate 111a of the hydraulic pump 111 is linked to a transmission arm 100a provided in the transmission case 100, and the angle of the movable swash plate 111a can be changed by rotating the transmission arm 100a. A transmission gear 115 is fixed to the pump output shaft 114 of the hydraulic pump 111, and power is transmitted to the charge pump 271 of the HMT 110 and the charge pump 272 of the elevating mechanism 230 at the end thereof.

A sun gear 121 is pivotally supported on the motor shaft 113 of the hydraulic motor 112, and a planetary carrier 122 is pivotally supported on a boss portion of the sun gear 121 so as to be freely rotatable, and three

planetary gears

123 and 123 around the sun gear 121 are supported. -123 is rotatably provided. Further, a ring gear 124 is externally fitted to and engaged with the three

planetary gears

123, 123, and 123. Thus, the planetary gear mechanism 120 is formed by the sun gear 121, the planetary carrier 122, the three

planetary gears

123, 123, 123, and the ring gear 124, and the power of the HST system and the power of the gear system are combined.

In such an HMT 110, by changing the angle of the movable swash plate 111a of the hydraulic pump 111 by rotating the transmission arm 100a, the hydraulic oil corresponding to the angle is sent from the hydraulic pump 111. The power (rotational speed) of the motor shaft 113 of the hydraulic motor 112 is changed according to the amount of oil fed from the hydraulic pump 111, and the sun gear 121 rotates at a speed corresponding to this power. On the other hand, when the pump output shaft 114 of the hydraulic pump 111 rotates, the transmission gear 115 and the planetary carrier 122 rotate, and the

planetary gears

123, 123, 123 rotate.

Thereafter, the planetary gear mechanism 120 combines the power of the sun gear 121 and the power of the

planetary gears

123, 123, 123 so that the combined output shaft 102 rotates or stops at a speed corresponding to the position of the speed change arm 100a. Become. In this way, the gear ratio of the HMT 110 is changed. The rotational speed of the combined output shaft 102 is a speed corresponding to the rotational speed of the engine 214 and the gear ratio of the HMT 110.

The main clutch 130 switches whether power can be transmitted from the HMT 110 to the composite output shaft 102. The main clutch 130 is interposed between the ring gear 124 and the composite output shaft 102. In the main clutch 130, the ring gear 124 and the composite output shaft 102 are connected or disconnected as the clutch shifter 131 slides. In this way, the power of the ring gear 124 is transmitted to the composite output shaft 102. Or it is not transmitted.

The main transmission mechanism 140 shifts the power from the HMT 110 in multiple stages. The main transmission mechanism 140 includes a reverse input gear 141, a forward gear 142, and a moving gear 143 that are sequentially fixed to the composite output shaft 102, a reverse output gear 144, and a reverse gear 145 that are fixed to the counter shaft 103, And a slider 146 slidably provided on the travel transmission shaft 104. The reverse input gear 141 and the reverse output gear 144 are engaged with each other, and the power of the combined output shaft 102 is always transmitted to the counter shaft 103.

The slider 146 is formed with a small diameter gear 146a and a large diameter gear 146b. The slider 146 slides on the traveling transmission shaft 104 by the operation of the main transmission lever 225, and the small-diameter gear 146a meshes with the forward gear 142 to advance, and the large-diameter gear 146b meshes with the moving gear 143. Thus, the large-diameter gear 146b meshes with the reverse gear 145 to reversely move, and the small-diameter gear 146a and the large-diameter gear 146b switch to neutral when the gear does not mesh with any gear.

The braking device 150 brakes the rotation of the traveling transmission shaft 104 that is the output shaft of the main transmission mechanism 140. The braking device 150 is provided at one end of the traveling transmission shaft 104. The braking device 150 is configured such that the braking device 150 can be operated by rotating the brake arm.

A front side transmission gear 161 is fixed to the other end of the traveling transmission shaft 104, and the front side transmission gear 161 meshes with an input gear of the differential device 162. The power of the travel transmission shaft 104 is transmitted to the left and right front output shafts 105 via the differential device 162, and the power transmitted to the left and right front output shafts 105 is transmitted to the transmission mechanism in the front axle case 216. Via the front wheel 212. The differential device 162 can be locked by the front differential lock device 163.

A rear side first transmission gear 171 is fixed in the middle of the travel transmission shaft 104, and the rear side first transmission gear 171 is loosely fitted to one end of the transmission shaft 106. The rear side second transmission gear 172 is meshed with a rear side third transmission gear 173 fixed to one end of the rear side transmission shaft 107. A bevel gear 174 is fixed to the other end of the rear transmission shaft 107, and a bevel gear 175 that meshes with the bevel gear 174 is fixed to one end of the rear output shaft 108. The power of the travel transmission shaft 104 is transmitted to the rear output shaft 108 via the rear side transmission shaft 107, and the power transmitted to the rear side transmission shaft 107 is transmitted via the transmission mechanism in the rear axle case 217. And transmitted to the rear wheel 213.

A PTO-side first transmission gear 181 is fixed to one end of the composite output shaft 102, and the PTO-side first transmission gear 181 is loosely fitted to the other end of the traveling transmission shaft 104. 182, and the PTO side second transmission gear 182 is engaged with a PTO side third transmission gear 183 fixed in the middle of the transmission shaft 106. A bevel gear 184 is fixed to the other end of the transmission shaft 106, and a bevel gear 185 that meshes with the bevel gear 184 is fixed to one end of the PTO output shaft 109. Then, the power of the combined output shaft 102 is transmitted to the PTO output shaft 109 via the transmission shaft 106.

The motive power transmitted to the PTO output shaft 109 is shifted by an increase / decrease gear or a transmission mechanism built in the inter-stock transmission case 251, and the lateral feed mechanism and each rotary case via a planting clutch, a planting mission case 247, etc. 244. As a result, the lateral feed mechanism is activated and the seedling stage 241 is slid in the left-right direction, and the rotary case 244 is rotated and the two planting claws 245 are alternately seedlings. It can be taken out from the seedling mat on 241 and planted in the field.

Hereinafter, the control configuration of the rice transplanter 200 will be described with reference to FIG.

As shown in FIG. 13, the shift pedal 226 is a shift operation tool for changing the working speed (traveling speed) of the rice transplanter 200. The transmission pedal 226 is disposed on the lower right side of the dashboard 221. The operation amount of the shift pedal 226 can be detected by a potentiometer 226a. The potentiometer 226a is configured to detect a rotation angle of a detection shaft that rotates by operating the speed change pedal 226. The potentiometer 226 a is connected to the control device 260 and transmits the detected value (the operation amount of the shift pedal 226) to the control device 260. In addition, it is also possible to use not a pedal but a lever or a push switch as a speed change operation tool.

The mode selection switch 227 is an operation tool for selecting the control mode of the rice transplanter 200. The mode selection switch 227 is provided on the dashboard 221. The mode selection switch 227 is configured so that the rice transplanter 200 can be selected from five control modes of “fuel efficiency mode”, “shift efficiency mode”, “exhaust gas reduction mode”, “load mode”, and “automatic mode”. . The mode selection switch 227 is connected to the control device 260 and transmits a signal corresponding to the selected control mode to the control device 260.

The control device 260 controls the first motor 261 and the second motor 262. The control device 260 is provided at an arbitrary position of the traveling unit 210. Specifically, the control device 260 may be configured such that a CPU, a ROM, a RAM, an HDD, and the like are connected by a bus, or may be configured by a one-chip LSI or the like. Various programs and maps for controlling the operations of the first motor 261 and the second motor 262 are stored in the control device 260 in advance.

The first motor 261 is an actuator for changing the rotational speed of the engine 214. Specifically, the first motor 261 is a brassless DC motor, a stepping motor, or the like. The first motor 261 is connected to the control device 260 and is driven based on a signal transmitted from the control device 260. The output shaft of the first motor 261 is connected to the speed governor 214a of the engine 214 via a link mechanism. The first motor 261 drives the speed governor 214a and can change the rotational speed of the engine 214. Note that the speed governor 214a also serves as an output detection unit for detecting the output of the engine 214.

The second motor 262 is an actuator for changing the gear ratio of the HMT 110. Specifically, the second motor 262 is a brassless DC motor, a stepping motor, or the like. The second motor 262 is connected to the control device 260 and is driven by a signal transmitted from the control device 260. The output shaft of the second motor 262 is connected to the speed change arm 100a via a link mechanism. The speed change arm 100a is rotated by the second motor 262, the inclination angle of the movable swash plate 111a of the hydraulic pump 111 is changed, and the speed change ratio of the HMT 110 can be changed.

The engine speed detecting means 263 detects the speed of the engine 214. The engine speed detection means 263 is configured to detect, for example, the speed of the flywheel or crankshaft of the engine 214. Specifically, the engine speed detection means 263 is configured by a magnetic pickup coil, a rotary encoder, or the like. The engine speed detection means 263 is connected to the control device 260 and transmits the detection signal to the control device 260.

In such a rice transplanter 200, the control device 260 controls the first motor 261 and the second motor 262 based on the detection value of the potentiometer 226a, thereby changing the traveling speed and work speed of the rice transplanter 200. can do. That is, the operability of the rice transplanter 200 is improved because the traveling speed and the working speed are changed by only one operating tool (shift pedal 226) instead of two operating tools as in the prior art. In addition, the rotational speed of the engine 214 and the gear ratio of the HMT 110 can be appropriately changed according to the traveling state of the rice transplanter 200, for example, the state of entering / exiting the farm field, the state of entering / exiting the truck, and the like. Also, the working situation of the rice transplanter 200, for example, the situation where the plant 214 is planted with a large amount of fuel consumed by the engine 214, the situation where the plant 214 is planted while the exhaust gas emission rate of the engine 214 is high, The speed of the engine 214 and the gear ratio of the HMT 110 can be appropriately changed according to the situation in which the planting operation is performed in the above state.

Hereinafter, specific control modes of the rice transplanter 200 will be described with reference to FIGS. 13 and 14.

FIG. 14 is a diagram showing the relationship between the rotational speed of the engine 214 and the net average effective pressure. The control device 260 stores a map shown in FIG. 14 in advance. Here, the net average effective pressure refers to an average value of the pressure in the cylinder during one cycle of the engine 214. The map shows the characteristics of the engine 214 and is derived in advance by a test or the like. FIG. 14 is an example, and the characteristics of the engine 214 are not limited to this.

The solid line in FIG. 14 shows the iso-fuel consumption curve of the engine 214. An equal fuel consumption curve is a measurement of fuel consumption per output of the engine 214 (hereinafter simply referred to as “fuel consumption”) for each engine speed and each net average effective pressure. Is connected. Of the equal fuel consumption curves in FIG. 14, the area within the innermost fuel consumption curve (hereinafter referred to as “minimum fuel consumption area”) has the smallest fuel consumption (good fuel consumption) and the outer equal fuel consumption curve. The fuel consumption increases toward the curve (fuel consumption is worse). That is, FIG. 14 is a map relating to fuel efficiency of the engine 214.

The control device 260 constantly calculates the net average effective pressure of the engine 214. That is, the control device 260 stores in advance a map indicating the relationship between the fuel injection pattern (for example, the fuel injection amount, the number of fuel injections, the fuel injection timing, etc.) of the governor 214a and the net average effective pressure. The net average effective pressure of the engine 214 is always calculated based on the map from the fuel injection pattern of the governor 214a.

In such rice transplanter 200, when the shift pedal 226 is operated after the “fuel efficiency mode” is selected by the mode selection switch 227, the control device 260 sets the operation amount of the shift pedal 226 detected by the potentiometer 226a. Based on this, the first motor 261 and the second motor 262 are controlled to change the rotational speed of the engine 214 and the gear ratio of the HMT 110, and consequently change the working speed (traveling speed). At this time, the control device 260 grasps the position corresponding to the state of the engine 214 in FIG. 14 from the engine speed detected by the engine speed detecting means 263 and the calculated net average effective pressure. 14, the first motor 261 and the second motor 262 are controlled so that the position corresponding to the state of the engine 214 in the engine 14 is within the minimum fuel consumption region or close to the minimum fuel consumption region.

For example, it is assumed that the rotational speed of the engine 214 is N1, the net average effective pressure is P1, and the position corresponding to the state of the engine 214 is X1. In such a case, as indicated by the white arrow, the control device 260 decreases the rotational speed of the engine 214 from N1 to N2 and increases the net average effective pressure from P1 to P2, thereby reducing X2 within the minimum fuel consumption region. The first motor 261 and the second motor 262 are controlled so as to be positioned at the position. In this way, by controlling the first motor 261 and the second motor 262 based on the map related to the fuel efficiency of the engine 214 and the detected value of the potentiometer 226a, the fuel consumption of the engine 214 can be achieved even at the same work speed. Can be suppressed, and fuel consumption can be improved.

Below, the modification of the specific control aspect of the rice transplanter 200 is demonstrated using FIG.13 and FIG.15.

FIG. 15 is a map relating to the speed change efficiency of the HMT 110, and more specifically, a map showing the relationship between the working speed of the rice transplanter 200 and the overall efficiency of the HMT 110. The total efficiency of the HMT 110 is the sum of the effective power of the hydraulic transmission mechanism constituted by the hydraulic pump 111 and the hydraulic motor 112 shown in FIG. 13 and the effective power of the gear transmission mechanism constituted by the transmission gear 115 and the planetary carrier 122. It is said. The map shows the characteristics of the HMT 110 and is derived in advance by a test or the like. Note that FIG. 15 is an example, and the characteristics of the HMT 110 are not limited thereto.

In such a rice transplanter 200, when the speed change pedal 226 is operated after the “speed change efficiency mode” is selected by the mode selection switch 227, the control device 260 sets the operation amount of the speed change pedal 226 detected by the potentiometer 226a. Based on this, the first motor 261 and the second motor 262 are controlled to change the rotational speed of the engine 214, the gear ratio of the HMT 110, and the work speed. At this time, the control device 260 controls the first motor 261 and the second motor 262 so that the overall efficiency of the entire HMT 110 is increased, that is, the conversion efficiency of the HMT 110 is improved.

For example, it is assumed that the work speed corresponding to the operation amount of the shift pedal 226 is V1, and the total efficiency of the HMT 110 at the work speed V1 is E1. In such a case, the control device 260 controls the second motor 262 so that the total efficiency E1 becomes the highest gear ratio, that is, the HMT 110 shifts only with the gear effective power. Then, the control device 260 calculates an appropriate number of revolutions of the engine 214 from the speed ratio at which the overall efficiency becomes the highest and the work speed V1 corresponding to the operation amount of the speed change pedal 226, and calculates the number of revolutions. Thus, the first motor 261 is controlled.

In this state, when the operation speed corresponding to the operation amount of the shift pedal 226 is changed from V1 to V2 by operating the shift pedal 226, and the total efficiency of the HMT 110 at the work speed V2 is E2, the control device 260 indicates the second motor 262 so that the overall efficiency E2 becomes the highest gear ratio as indicated by the white arrow, that is, the HMT 110 shifts only with the gear effective power as in the case of V1. Control. Then, the control device 260 controls the first motor 261 so that the rotational speed of the engine 214 corresponds to the speed ratio at which the overall efficiency becomes the highest and the work speed V2. In this way, by controlling the first motor 261 and the second motor 262 based on the map related to the shift efficiency of the HMT 110 and the detected value of the potentiometer 226a, the overall efficiency in the HMT 110 is high in the entire work speed region. Work can be done.
Note that when a small speed change is required on the low speed side, the ratio of the effective hydraulic power to the total efficiency can be increased.

Below, the modification of the specific control aspect of the rice transplanter 200 is demonstrated using FIG.13 and FIG.16.

FIG. 16 is a map relating to the exhaust gas emission rate of the engine 214, and more specifically, a map showing the relationship between the rotational speed of the engine 214 and the NOx concentration in the exhaust gas. The control device 260 stores in advance a map shown in FIG. The map shows the characteristics of the engine 214 and is derived in advance by a test or the like. FIG. 16 is an example, and the characteristics of the engine 214 are not limited thereto. Moreover, the map which shows PM density | concentration and HC density | concentration in waste gas may be sufficient.

In such a rice transplanter 200, when the shift pedal 226 is operated after the “exhaust gas efficiency mode” is selected by the mode selection switch 227, the control device 260 sets the operation amount of the shift pedal 226 detected by the potentiometer 226a. Based on this, the first motor 261 and the second motor 262 are controlled to change the rotational speed of the engine 214 and the gear ratio of the HMT 110, thereby changing the working speed. At this time, the control device 260 controls the first motor 261 and the second motor 262 so that the NOx concentration in the exhaust gas decreases based on the map.

For example, when the rotational speed of the engine 214 is N3 and the NOx concentration corresponding to the rotational speed N3 is C1, the control device 260 indicates that the rotational speed of the engine 214 is N3 as indicated by a white arrow. The first motor 261 is controlled to increase from NO to N4, and the NOx concentration is decreased to C2. Then, the control device 260 calculates an appropriate gear ratio of the HMT 110 from the rotational speed N4 of the engine 214 and the work speed corresponding to the operation amount of the shift pedal 226, and the second gear ratio is set so as to be this gear ratio. The motor 262 is controlled. In this way, by controlling the first motor 261 and the second motor 262 based on the map related to the exhaust gas efficiency of the engine 214 and the detected value of the potentiometer 226a, the NOx concentration is lowered even at the same work speed. This makes it possible to reduce exhaust gas.

Hereinafter, a modified example of a specific control mode of the rice transplanter 200 will be described with reference to FIGS. 13 and 17.

FIG. 17 is a map relating to the load factor of the engine 214, and more specifically, a map showing the relationship between the rotational speed of the engine 214 and the output (load) of the engine 214. The control device 260 stores a map shown in FIG. 17 in advance. The solid line in FIG. 17 is an output curve connecting points that are the maximum output at each rotation speed. On this output curve, the load factor of the engine 214 (the ratio of the actual output to the maximum output of the engine 214) is 100. %. A lower region in the output curve in FIG. 17 is an operation region where the engine 214 operates, and an upper region is a stop region where the engine 214 stops. The map shows the characteristics of the engine 214 and is derived in advance by a test or the like. Note that FIG. 17 is an example, and the characteristics of the engine 214 are not limited thereto.

The control device 260 constantly calculates the output of the engine 214. That is, the control device 260 stores in advance a map indicating the relationship between the fuel injection pattern (for example, the fuel injection amount, the number of fuel injections, the fuel injection timing, etc.) of the governor 214a and the engine output, Based on the map, the output of the engine 214 is constantly calculated from the fuel injection pattern of the governor 214a.

In such a rice transplanter 200, when the shift pedal 226 is operated after the “load mode” is selected by the mode selection switch 227, the control device 260 is based on the operation amount of the shift pedal 226 detected by the potentiometer 226a. Then, the first motor 261 and the second motor 262 are controlled to change the rotational speed of the engine 214, the gear ratio of the HMT 110, and the work speed. At this time, even when an excessive load is applied to the engine 214 due to mud, grooves, inclination, etc., the control device 260 detects the engine speed detected by the engine speed detection means 263 and the calculated engine output. 17, the position corresponding to the state of the engine 214 in FIG. 17 is grasped, and the position corresponding to the state of the engine 214 in FIG. The motor 262 is controlled.

For example, it is assumed that the rotational speed of the engine 214 is N5, the output of the engine 214 is W1, and the position corresponding to the state of the engine 214 is Y1. In such a case, when an excessive load is applied to the engine 214 (the output of the corresponding engine 214 is W2) and the rotational speed of the engine 214 decreases, the control device 260 operates the position corresponding to the state of the engine 214. The rotational speed of the engine 214 is increased from N5 to N6 so as to be located at Y2 in the region (the two-dot chain arrow in FIG. 17), and the work corresponding to the rotational speed N6 and the operation amount of the shift pedal 226 Based on the speed, an appropriate gear ratio of the HMT 110 is calculated, and the first motor 261 and the second motor 262 are controlled to achieve this gear ratio. As described above, even when the engine 214 is overloaded due to inclination or the like by controlling the first motor 261 and the second motor 262 based on the map relating to the load factor of the engine 214 and the detected value of the potentiometer 226a. The work speed does not decrease, and the work can be performed reliably.

Further, when “automatic mode” is selected by the mode selection switch 227, among the four control modes (“fuel efficiency mode”, “transmission efficiency mode”, “exhaust gas reduction mode”, “load mode”), rice transplanting is performed. An appropriate control mode is automatically selected according to the traveling state and working state of the machine 200. For example, during normal work, the work is performed in the “fuel efficiency mode”, and when the engine 214 is overloaded due to mud, grooves, inclination, etc., it is automatically switched to the “load mode”.

It should be noted that the rice transplanter 200 can be configured to serve as a plurality of control modes. For example, the fuel consumption can be further reduced by combining the “fuel efficiency mode” and the “conversion efficiency mode”. In addition, by combining the “exhaust gas efficiency mode” and the “load mode”, it is possible to reliably perform work even when the engine 214 is overloaded due to inclination or the like while reducing exhaust gas.

In addition, the rice transplanter 200 can arbitrarily change the rotational speed of the engine 214 and the gear ratio of the HMT 110 by individually controlling the first motor 261 and the second motor 262, so that the engine does not pass through the HMT 110. It is also possible to configure so that power is transmitted to the PTO output shaft 109 by branching from 214. For example, as shown in FIG. 18, a bevel gear 191 is fixed to the pump output shaft 114 of the hydraulic pump 111, and a bevel gear 192 that meshes with the bevel gear 191 is fixed to one end of the PTO output shaft 109. Power is transmitted to the PTO output shaft 109 without being shifted by the HMT 110.

In this case, the control device 260 can change the rotational speed of the PTO output shaft 109 to an arbitrary rotational speed by controlling the first motor 261 and changing the rotational speed of the engine 214. Therefore, an increase / decrease gear and a transmission mechanism built in the inter-stock transmission case 251 are not required, and the cost can be reduced. Note that the control device 260 controls the second motor 262 so that the speed ratio of the HMT 110 corresponding to the rotation speed of the engine 214 and the operation amount (working speed) of the speed change pedal 226 is obtained.

Similarly, it is also possible to configure so that power is transmitted from the engine 214 to the traveling transmission shaft 104. This eliminates the need for the speed increasing / decreasing gear and the speed change mechanism on the traveling side, thereby reducing the cost.

As described above, in the rice transplanter 200, the engine 214, the first motor 261 serving as the first actuator for changing the rotational speed of the engine 214, and the continuously variable transmission for shifting the power from the engine 214 are provided. HMT 110, a second motor 262 serving as a second actuator for changing a gear ratio of the HMT 110, a shift pedal 226 serving as a shift operating tool for changing a traveling speed, and an operation amount for detecting an operation amount of the shift pedal 226 The rice transplanter 200 includes a potentiometer 226a serving as a detection unit, and a control device 260 that controls the first motor 261 and the second motor 262 based on a detection value of the potentiometer 226a. Thereby, the traveling speed and work speed of the rice transplanter 200 can be changed by controlling the first motor 261 and the second motor 262 based on the detection value of the potentiometer 226a. Therefore, the operator can change the traveling speed and work speed of the rice transplanter 200 with only the shift pedal 226, and the operability is improved. Further, the rotational speed of the engine 214 and the gear ratio of the HMT 110 can be appropriately changed according to the traveling situation and work situation of the rice transplanter.

Further, the control device 260 includes a map relating to fuel efficiency of the engine 214, a map relating to the shift efficiency of the HMT 110, a map relating to the exhaust gas emission rate of the engine 214, and a map relating to the load factor of the engine 214. At least one of them is stored, and the first motor 261 and the second motor 262 are controlled based on the stored map and the detected value of the potentiometer 226a. Thereby, fuel consumption can be improved by controlling the 1st motor 261 and the 2nd motor 262 based on the map concerning fuel consumption efficiency. Further, by controlling the first motor 261 and the second motor 262 based on the map related to the shift efficiency, the shift efficiency can be improved in the entire speed range. Moreover, exhaust gas can be reduced by controlling the 1st motor 261 and the 2nd motor 262 based on the map which concerns on an exhaust gas discharge rate. Further, by controlling the first motor 261 and the second motor 262 based on the map related to the load factor of the engine 214, it is possible to reliably travel even when the engine 214 is overloaded due to inclination or the like.

Also, power is transmitted from the engine 214 to the PTO output shaft 109 by branching. Thereby, the rotational speed of the PTO output shaft 109 can be changed by changing the rotational speed of the engine 214. Therefore, the speed increasing / decreasing gear and the speed change mechanism are not required, and the cost can be reduced.

Claims

An actuator for changing the engine speed and / or the gear ratio of the HST;
Transmission means that is an operating tool for changing the drive amount of the actuator;
A control device that is connected to the actuator and the speed change means, and changes the vehicle speed by changing at least one of the rotational speed of the engine and the speed ratio of the HST by the actuator based on an operation amount of the speed change means;
A maximum speed setting means that is connected to the control device and is an operating tool for changing a maximum speed that is a vehicle speed when the speed change means is operated up to a maximum operation amount;
The controller is
The target drive amount of the actuator is calculated based on the operation amount of the speed change means, and the actuator is driven so that the drive amount of the actuator becomes the target drive amount. Change the size to correspond to
By changing the target drive amount of the actuator when the speed change means is operated to the maximum operation amount to a size corresponding to the operation amount of the maximum speed setting means, the maximum speed is set to the maximum speed setting means. Change to the size corresponding to the operation amount,
Rice transplanter.
The maximum speed setting means can be rotated, and within the rotation range, the variable range for changing the maximum speed corresponding to the amount of change of the rotation angle, and the change of the rotation angle A constant speed region for maintaining the maximum speed at a constant value,
The rice transplanter according to claim 1.
The constant speed range has a minimum speed range, a maximum speed range, and a sparse recommended speed range provided between the minimum speed range and the maximum speed range,
The variable range includes a first variable range provided between the minimum speed range and a sparse vegetation recommended speed range, and a second variable range provided between the sparse vegetation recommended speed range and a maximum speed.
The rice transplanter according to claim 2.
An actuator for changing the engine speed and / or the gear ratio of the HST;
Transmission means that is an operating tool for changing the drive amount of the actuator;
A control device that is connected to the actuator and the speed change means, and changes the vehicle speed by changing at least one of the rotational speed of the engine and the speed ratio of the HST by the actuator based on an operation amount of the speed change means;
Maximum speed setting means that is connected to the control device and is an operating tool for changing a maximum speed that is a vehicle speed when the speed change means is operated to a maximum operation amount;
A speed fixing means connected to the control device, and being an operating tool for fixing the vehicle speed to a constant value regardless of the operation of the speed change means;
The controller changes the drive amount of the actuator based on the operation amount of the maximum speed setting means when the vehicle speed is fixed by the speed fixing means and the maximum speed setting means is operated. By changing the vehicle speed fixed by the speed fixing means to a size corresponding to the operation amount of the maximum speed setting means,
Rice transplanter.
When the vehicle speed is fixed by the speed fixing unit and the vehicle speed after the change by the maximum speed setting unit is less than a predetermined speed lower limit threshold, the control device fixes the vehicle speed by the speed fixing unit. ,
The rice transplanter according to claim 4.
The controller is
When the vehicle speed is fixed by the speed fixing means, the speed fixing is performed when the operation amount of the speed change means decreases to less than a predetermined fixed release lower limit and then increases to the fixed release lower limit. Release the vehicle speed fixed by means,
When the vehicle speed is fixed by the speed fixing means and the operation amount of the speed change means increases to a predetermined unlocking upper limit value, the vehicle speed fixing by the speed fixing means is released,
The fixed release lower limit value is a value smaller than a fixed storage position that is an operation amount of the transmission unit when the speed fixing unit is operated and vehicle speed is fixed.
The fixed release upper limit value is a value larger than the fixed storage position.
The rice transplanter according to claim 4 or 5.
When the vehicle speed is fixed by the speed fixing means and the maximum speed setting means is operated, the control device, when the maximum speed setting means is operated, the fixed release lower limit value and a fixed value according to the operation amount of the maximum speed setting means Change the cancellation upper limit,
The rice transplanter according to claim 6.