JP2010216563A - Maximum speed control mechanism for work vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a maximum speed control mechanism constructed to control the drive of a transmission actuator to change the moving speed, including a maximum speed setter for limiting a maximum moving speed to improve the operability and travelling performance of a work vehicle. <P>SOLUTION: A rice transplanter 1 includes a traveling body 3 mounted with an engine 5, a continuously variable transmission, a transmission pedal 16 (a transmission operator), the transmission actuator for controlling the transmission of the continuously variable transmission in accordance with the operation amount of the transmission pedal (the transmission operator). The maximum speed control mechanism for the rice transplanter (the work vehicle) includes the maximum speed setter for limiting the maximum moving speed when operating the transmission pedal (the transmission operator) to a maximum. The maximum moving speed can be limited during traveling on a road or the tilting of the traveling body. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technology of a maximum speed control mechanism for a work vehicle that changes a moving speed by performing a shift control of a continuously variable transmission using a shift actuator.

  Conventionally, a rice transplanter (work vehicle) is known in which a continuously variable transmission (device) is shift-controlled by a shift actuator to change a moving speed (for example, see Patent Document 1). The rice transplanter in Patent Document 1 detects the amount of stepping operation of the shift pedal with a pedal position sensor (detection means), and drives the speed change actuator so that the arm of the continuously variable transmission is located at a position corresponding to the amount of stepping operation. By performing the control, the shift control of the continuously variable transmission is performed. That is, the rice transplanter in Patent Document 1 increases the engine speed in proportion to the operation of depressing the shift pedal.

Japanese Patent No. 4095356

  However, the rice transplanter (work vehicle) of Patent Document 1 increases the engine speed in proportion to the operation of depressing the speed change pedal. Regardless of the difference, etc., when the amount of depressing operation of the shift pedal is the same, the moving speed is the same. For this reason, there is a problem that it is difficult to perform stable maneuvering and traveling when a pilot with low skill level is maneuvering, or when traveling in a place with poor traveling conditions such as a sloping ground.

  The present invention has been made to solve such a problem, and includes a maximum speed setting device for limiting the maximum moving speed in a configuration in which the speed of the continuously variable transmission is controlled by a shift actuator to change the moving speed. An object of the present invention is to provide a maximum speed control mechanism for a work vehicle that has good operability and traveling performance.

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

That is, the maximum speed control mechanism of the work vehicle according to the first invention is:
In a work vehicle comprising: a traveling machine body on which an engine is mounted; a continuously variable transmission; a transmission operation tool; and an actuator that controls the transmission of the continuously variable transmission based on an operation amount of the transmission operation tool.
A maximum speed setting device for limiting the maximum movement speed when the shift operation tool is operated to the maximum is provided, and the maximum movement speed can be limited by traveling on the road or tilting the traveling machine body.

The maximum speed control mechanism of the work vehicle according to the second invention is the maximum speed control mechanism of the work vehicle according to the first invention,
A tilt sensor for detecting the tilt of the traveling machine body, and when the detection result of the tilt sensor is equal to or greater than a predetermined value, the maximum movement speed is made lower than when the detection result of the tilt sensor is less than the predetermined value. It is composed.

The maximum speed control mechanism of the work vehicle according to the third invention is the maximum speed control mechanism of the work vehicle according to the first invention,
A steering sensor for a steering wheel is provided, and when the detection result of the steering sensor is equal to or greater than a predetermined value, the maximum movement speed is lower than when the detection result of the steering sensor is less than a predetermined value. is there.

The maximum speed control mechanism of the work vehicle according to the fourth invention is the maximum speed control mechanism of the work vehicle according to the first invention,
When the detection result of one or both of the water temperature sensor of the engine and the oil temperature sensor of the continuously variable transmission is greater than or equal to a predetermined value, the maximum moving speed is lower than when the detection result is less than the predetermined value. It is comprised as follows.

  As effects of the present invention, the following effects can be obtained.

  In the first invention, the maximum speed value can be changed according to the driver's preference and the driving conditions (flat ground and sloping ground). If the conditions are bad, even if the shift pedal is operated to the maximum, the vehicle does not travel at high speed, so that the maneuverability and travelability can be improved.

  In the second aspect of the invention, when the traveling machine body is largely tilted back and forth or left and right, the maximum moving speed is automatically lowered, so that it is possible to prevent the moving speed from being improperly increased even if a gear shift operation is mistakenly performed. .

  In the third aspect of the invention, when the steering handle is rotated to largely change the direction of the traveling machine body, the maximum moving speed is automatically lowered. Can be prevented.

  In the fourth invention, when the temperature of the engine or continuously variable transmission becomes high during the planting operation, the maximum moving speed is automatically lowered, so the engine or continuously variable transmission is overloaded. (Overheating) can be prevented.

The side view of the rice transplanter which concerns on 1st Embodiment. The top view of the rice transplanter which concerns on 1st Embodiment. Schematic of a traveling speed change mission. Schematic which shows the relationship between a driving operation part and a driving | running | working transmission mission. FIG. 5 is an enlarged sectional view taken along line VV in FIG. 4. FIG. 6 is an enlarged sectional view taken along line VI-VI in FIG. 4. The block diagram which shows the control structure of the control apparatus of a rice transplanter. The flowchart which shows control of the maximum speed control mechanism of the rice transplanter 1 with respect to the driving conditions (flat ground and sloping ground) of the rice transplanter. The flowchart which shows control of the maximum speed control mechanism of the rice transplanter 1 with respect to the driving | running | working state (traveling direction) of the rice transplanter. The flowchart which shows control of the maximum speed control mechanism of the rice transplanter 1 with respect to the temperature of the engine 5 and the continuously variable transmission 21. FIG.

  Hereinafter, an embodiment of the present invention will be described using a work vehicle according to the present invention as a rice transplanter. The work vehicle according to the present invention is not limited to a rice transplanter, and may be other agricultural work vehicles, construction work vehicles, or the like.

  First, the overall configuration of the rice transplanter 1 will be described with the arrow A direction in FIG.

  As shown in FIGS. 1 and 2, the rice transplanter 1 includes a multi-row planting seedling planting device 2 and a traveling machine body 3. The seedling planting device 2 is attached to the rear portion of the traveling machine body 3 so as to be rotatable in the vertical direction, and is configured so that the seedlings on the seedling mounting table 2a can be planted on the field by a plurality of seedling planting claws 2b at an appropriate vertical position. Is done.

In the traveling machine body 3, the vehicle body frame 4 is supported by a pair of left and right front wheels 6 and a pair of left and right rear wheels 7. The vehicle body frame 4 is equipped with an engine 5 and a traveling speed change mission 20.
The engine 5 is covered with a bonnet 9 on the front side of the body frame 4. Then, the output of the engine 5 is appropriately shifted by the traveling shift transmission 20 and then transmitted to the wheels 6 and 7. Thereby, the traveling machine body 3 is allowed to travel.

  The vehicle body frame 4 is provided with a driving operation unit 10. The driving operation unit 10 includes a seat 12, a steering handle 13, a transmission lever 14, a display panel 15, a transmission pedal 16, a brake pedal 17, and the like. The speed change pedal 16 and the brake pedal 17 are forward pedals, and are arranged on the right and left sides of the driving operation unit 10 on the right side of the steering handle 13 and pivotally attached to the vehicle body frame 4. The transmission pedal 16 is an embodiment of the “transmission operation tool” according to the present invention.

  As shown in FIG. 2, the display panel 15 is disposed in the vicinity of the steering handle 13. The display panel 15 is provided with display means for displaying the airframe status, and in the event of problems such as abnormal operation of the speed change actuator 60 described later, cutting of seedlings and fertilizers, and clogging of fertilizers, this is indicated to the operator. An informing means for informing is provided.

  For example, the notification means is configured such that a display lamp (not shown) is provided in the main body of the display panel 15 and is lit or blinks when the above-described malfunction occurs. However, the notification means is configured such that a buzzer or the like is provided in the main body of the display panel 15 so that a notification sound is generated when the above-described problem occurs, or the content of the malfunction is displayed on the liquid crystal screen or the like of the display panel 15. It is also possible to configure in this way. Further, the notification means is not limited to the display panel 15 and may be provided in another member.

  Next, a configuration for performing a shift will be described.

  As shown in FIG. 3, the traveling transmission mission 20 is provided with a hydraulic continuously variable transmission 21. The continuously variable transmission 21 has a variable displacement hydraulic pump 24 driven by the output of the engine 5 and a hydraulic motor 25 driven by the hydraulic pressure from the hydraulic pump 24, and a swash plate in the hydraulic pump 24. By changing the inclination angle of 24a, the discharge amount of hydraulic oil is changed, the rotation speed of the output shaft of the hydraulic motor 25 is changed, and the moving speed of the traveling machine body 3 is changed.

  In this embodiment, the hydraulic continuously variable transmission 21 is combined with the mechanical transmission 40 including a planetary gear mechanism to form a hydraulic / mechanical continuously variable transmission.

  Further, as shown in FIGS. 4 and 6, a speed change operation shaft 63 extends in the lateral direction at the front portion of the vehicle body frame 4 and is rotatably supported by a bearing. A sector gear 62 is fixed to the speed change operation shaft 63, and the sector gear 62 and the speed change operation shaft 63 can be rotated together. An arm 65 is fixed to the speed change operation shaft 63 at the base end portion thereof, and the arm 65 and the speed change operation shaft 63 can be integrally rotated.

  A pinion 61 is engaged with the sector gear 62 on the speed change operation shaft 63. The pinion 61 can be rotated by a speed change actuator 60 made of an electric motor, and the speed change operation shaft 63 is rotated in the direction of arrow C in FIG. 6 or the direction of arrow D in FIG. It is configured to be able to.

  On the other hand, a front end portion of a speed change rod rod 67 extending in the front-rear direction is pivotally attached to the distal end portion of the arm 65 on the speed change operation shaft 63. A long slot 67a is formed in the rear end portion of the transmission rod rod 67 with a predetermined length in the front-rear direction. A pin 47a provided at the front end of the speed change arm 47 of the continuously variable transmission 21 is slidably fitted into the long groove hole 67a so that the rear end of the speed change rod rod 67 and the front end of the speed change arm 47 are engaged. Combined. The base of the speed change arm 47 is linked to the swash plate 24a of the hydraulic pump 24 via a trunnion shaft.

  Thus, the continuously variable transmission 21 is configured such that when the speed change operation shaft 63 is not rotated and the speed change rod rod 67 is not moved backward, or when the speed change operation shaft 63 is rotated and the speed change rod rod 67 is moved rearward. However, when the movement amount does not exceed the predetermined length of the long slot 67a, the swash plate 24a of the hydraulic pump 24 is set to the neutral position without being tilted by the speed change arm 47 and the trunnion shaft, and directed toward the wheels 6 and 7. Thus, it is configured to be in a neutral state where no output is transmitted.

  In the continuously variable transmission 21, the speed change rod 63 is rotated in the direction of the arrow C in FIG. 6 with the speed change rod 67 being hardly moved rearward, and the speed change rod 67 is moved rearward. When the movement amount of the hydraulic pump 24 exceeds the predetermined length of the long slot 67a, the swash plate 24a of the hydraulic pump 24 is moved from the point of time to the rear of the transmission rod rod 67 by the transmission arm 47 and the trunnion shaft. By tilting, the gear ratio is changed to the speed increasing side, and the moving speed is continuously increased.

  In the continuously variable transmission 21, the speed change rod 63 is rotated in the direction of arrow D in FIG. When 67 is moved forward, the swash plate 24a of the hydraulic pump 24 is moved by the transmission arm 47 and the trunnion shaft while the rearward movement amount of the transmission rod rod 67 exceeds the predetermined length of the long slot 67a. The shift rod rod 67 is tilted based on the forward movement amount, the gear ratio is changed to the deceleration side, and the movement speed is continuously reduced.

  The shift operation shaft 63 is provided with second detection means 66 for detecting the tilt angle of the swash plate 24a of the hydraulic pump 24 in the continuously variable transmission 21 (the rotation angle of the shift actuator 60). The second detection means 66 is composed of an angle sensor such as a potentiometer, and is configured to detect the rotation angle of the speed change operation shaft 63.

  In addition, a shift pedal shaft 51 extends laterally at the front portion of the vehicle body frame 4 and is rotatably supported by a bearing. The shift pedal 16 is linked to the shift pedal shaft 51 via the linkage mechanism 50.

  The speed change pedal 16 is urged by a spring means as an urging means made of an elastic body so that the front part is in a high oblique state on the floor surface of the driving operation part 10 with the rear part as a rotation fulcrum. This state is the initial position. For this speed change pedal 16, a stepping operation in which the operator depresses the speed change pedal 16 in the initial position with his / her foot forward, and a stepping release operation for removing the foot from the speed change pedal 16 in the state in which the driver has stepped on is performed. Is called.

  When the depressing operation is performed, the shift pedal 16 is rotated forward from the initial position against the spring means to rotate the shift pedal shaft 51 in the direction of arrow E in FIG. 5, while the depressing operation is performed. And is returned to the original initial position by the spring means, and is configured to rotate the shift pedal shaft 51 in the direction of arrow F in FIG.

  The shift pedal shaft 51 is provided with first detection means 55 for detecting the depression operation amount of the shift pedal 16. The first detection means 55 includes an angle sensor such as a potentiometer, and is configured to detect the rotation angle of the shift pedal shaft 51.

  Further, the traveling transmission mission 20 is provided with a clutch mechanism 22 for enabling transmission or interruption of the output from the hydraulic continuously variable transmission 21 to the wheels 6 and 7, and also applies braking force to the wheels 6 and 7. A brake mechanism 23 is provided.

  The travel transmission mission 20 is provided with a rotary operation shaft 45 for the brake mechanism 23. An operation member 46 is fixed to the operation shaft 45, and the operation member 46 and the operation shaft 45 can be rotated together. The operating member 46 is not only linked to the brake mechanism 23 but also linked to the clutch mechanism 22 via a wire or the like.

  A brake on / off member 75 provided in the traveling machine body 3 is interlocked with the brake mechanism 23.

  When the operation member 46 rotates together with the operation shaft 45 and is in a predetermined rotation position, the operation member 46 is in a stop state in which the brake mechanism 23 is in an operation state and the clutch mechanism 22 is in a disengagement state. At a certain time, the brake mechanism 23 is brought into a non-operating state, and at the same time, the clutch mechanism 22 is put into a running state. The actuating member 46 is biased so as to be in a traveling state by a spring means.

  Thus, the receiving member 46 a is integrally provided on the operating member 46 for both the clutch mechanism 22 and the brake mechanism 23. A speed change rod rod 67 is slidably inserted in the receiving piece 46a in the front-rear direction. A stopper piece 67b is provided in a portion of the speed change rod rod 67 positioned rearward of the receiving piece 46a so that the stopper piece 67b and the receiving piece 46a can come into contact with each other.

  When the speed change operation shaft 63 is not rotated and the speed change rod rod 67 is not moved backward, that is, when the speed change pedal 16 is held at the initial position and the stepping operation is not performed, the actuating member 46 resists the spring means. As described above, the rotation is restricted by contacting the stopper piece 67b, and the brake mechanism 23 is kept in the operating state and at the same time the clutch mechanism 22 is kept in the stopped state.

  When the speed change operation shaft 63 is rotated and the speed change rod rod 67 is moved rearward, that is, when the speed change pedal 16 is depressed and the speed change actuator 60 is driven to rotate as described later, the actuating member 46 is Along with the backward movement of the stopper piece 67b, the stopper member 67b is rotated by the spring means, so that the brake mechanism 23 is brought into a non-actuated state and at the same time the clutch mechanism 22 is brought into an on state.

  A brake shaft 70 extends in the lateral (left and right) direction at the front portion of the body frame 4 and is rotatably supported by a bearing. The brake pedal 17 is interlocked with the brake shaft 70.

  The brake pedal 17 is urged by a spring means as an urging means composed of an elastic body so that the front part is in a high oblique state on the floor surface of the driving operation part 10 with the rear part as a rotation fulcrum. This state is the initial position. With respect to the brake pedal 17, a stepping operation in which the operator depresses the brake pedal 17 in the initial position with his / her foot forward, or a stepping release operation in which the foot is removed from the brake pedal 17 in a state in which the operator has depressed the pedal. Is done.

  When the stepping operation is performed, the brake pedal 17 is rotated forward from the initial position against the spring means, and the brake shaft 70 is rotated in the direction of arrow M in FIG. The spring means is rotated rearward and returned to the original initial position, and the brake shaft 70 is configured to rotate in the direction opposite to the arrow M direction in FIG.

  An arm 71 is fixed to the brake shaft 70 at its base end. A front end portion of a brake rod rod 72 extending in the front-rear direction is pivotally attached to the distal end portion of the arm 71. The rear end portion of the brake rod rod 72 is inserted into the locking piece 46b of the operating member 46 so as to be slidable in the front-rear direction.

  The locking piece 46 b is provided integrally with the operating member 46. A stopper 72a is provided at a portion of the brake rod rod 72 positioned rearward of the locking piece 46b, and the stopper 72a and the locking piece 46b can be brought into contact with each other.

  When the brake shaft 70 is not rotated and the brake rod rod 72 is not moved forward, that is, when the brake pedal 17 is held at the initial position and the depression operation is not performed, the brake mechanism 23 of the operating member 46 is in an operating state. At the same time, free operation is permitted from a stopped state in which the clutch mechanism 22 is disengaged to a traveling state in which the brake mechanism 23 is inactivated and at the same time the clutch mechanism 22 is in the engaged state. Therefore, when the shift pedal is depressed, the driving state is changed as described above.

  When the brake shaft 70 is rotated and the brake rod rod 72 is moved forward (in the direction of the arrow L), that is, when the brake pedal 17 is depressed, the actuating member 46 puts the brake mechanism 23 into a non-actuated state. At the same time, if the vehicle is in a traveling state in which the clutch mechanism 22 is in the engaged state, it is rotated against the spring means, regardless of the movement position of the speed change rod rod 67, that is, in preference to the stepping operation of the speed change pedal 16. Forcibly changed to a stopped state.

  The traveling machine body 3 is provided with a control device 80 (FIG. 7). The control device 80 is connected to a first detection means 55, a second detection means 66, a speed change actuator 60 composed of an electric motor, and a brake on / off member 75.

  The control device 80 detects the depression operation amount of the shift pedal 16 based on the first detection means 55, and the tilt angle of the swash plate 24a of the hydraulic pump 24 in the continuously variable transmission 21 is preset based on the detection result. The speed change actuator 60 is rotationally driven so that the set angle is set. The control device 80 is also configured to detect the tilt angle of the swash plate 24 a of the hydraulic pump 24 based on the second detection means 66.

  In such a configuration, when the depressing operation of the speed change pedal 16 is not performed, the speed change operation shaft 63 is not rotated by the speed change actuator 60, and the speed change rod rod 67 is not moved backward. Therefore, the transmission arm 47 of the continuously variable transmission 21 in the traveling transmission 20 is not rotated, and the swash plate 24a of the hydraulic pump 24 of the continuously variable transmission 21 is held in the neutral position. That is, the continuously variable transmission 21 is in a neutral state in which power is not transmitted toward the wheels 6 and 7.

  Moreover, when the shift pedal 16 is not depressed, the brake mechanism 23 enters the braking state and the clutch mechanism 22 enters the disengaged state. As a result, the output from the continuously variable transmission 21 (hydraulic / mechanical continuously variable transmission) to the wheels 6 and 7 is cut off. Therefore, the traveling machine body 3 is stopped without traveling.

  When the shift pedal 16 is depressed when the traveling machine body 3 is in the stopped state, the shift pedal shaft 51 rotates in the direction of arrow E in FIG. 5, and the first detection means 55 rotates the shift pedal shaft 51. Detect the rotation angle. The control device 80 acquires the detection value of the first detection means 55 and detects the depression operation amount of the shift pedal 16 based on the detection value.

  Then, based on the amount of depression of the shift pedal 16, the control device 80 drives the shift actuator 60 to rotate. As the speed change actuator 60 is driven to rotate, the speed change operation shaft 63 rotates in the direction of arrow C in FIG. 6, and the speed change rod rod 67 starts to move in the direction of arrow G in FIG.

  When the rearward movement amount of the transmission rod rod 67 exceeds the predetermined length of the long slot 67a on the rear end side, the stopper piece 67b moves rearward. As a result, the actuating member 46 whose rotation by the spring means is restricted by the stopper piece 67b rotates, and the brake mechanism 23 becomes inoperative, and at the same time, the clutch mechanism 22 becomes engaged, whereby the continuously variable transmission. The power can be transmitted from the wheel 21 to the wheels 6 and 7.

  At this time, the speed change arm 47 rotates rearward, and the swash plate 24a of the hydraulic pump 24 in the continuously variable transmission 21 has a trunnion so that the tilt angle thereof becomes a set angle corresponding to the stepping operation amount of the speed change pedal 16. Tilt through the axis. Thereby, the continuously variable transmission 21 changes the gear ratio to the speed increasing side, and transmits the shifted power to the wheels 6 and 7. Therefore, the traveling machine body 3 starts traveling.

  In this state, when the depressing operation of the shift pedal 16 is performed, the shift pedal shaft 51 rotates in the direction of arrow F in FIG. 5, and the first detection means 55 detects the rotation angle of the shift pedal shaft 51 due to this rotation. To do. The control device 80 acquires the detection value of the first detection means 55 and detects the depression operation amount of the shift pedal 16 based on the detection value.

  Then, based on the operation amount of the shift pedal 16, the control device 80 drives the shift actuator 60 to rotate in the opposite direction. As the speed change actuator 60 is driven to rotate, the speed change operation shaft 63 rotates in the direction of arrow D in FIG. 6, and the speed change rod rod 67 moves in the direction of arrow H in FIG.

  As the transmission rod rod 67 moves forward, the transmission arm 47 rotates forward, and the tilt angle of the swash plate 24a of the hydraulic pump 24 in the continuously variable transmission 21 becomes the amount of depression of the transmission pedal 16. It tilts through the trunnion shaft so that the corresponding setting angle is obtained. As a result, the continuously variable transmission 21 changes its gear ratio to the deceleration side and transmits the shifted output to the wheels 6 and 7. Therefore, the speed of the traveling machine body 3 is reduced.

  When the transmission pedal 16 returns to the original initial position, the transmission arm 47 also returns to the original position, and the swash plate 24a of the hydraulic pump 24 of the continuously variable transmission 21 is set to the neutral position. Therefore, the traveling of the traveling machine body 3 is stopped.

  Next, a configuration for changing the rotational speed of the engine 5 will be described.

  As shown in FIG. 6, the cam groove 62 a is formed in an arc shape in the sector gear 62. Here, the cam groove 62a has a start end (low speed side) arranged at a predetermined distance from the speed change operation shaft 63 that is the center of the sector gear 62, while a terminal end (high speed side) is the start end (low speed side). Further, it is arranged closer to the speed change operation shaft 63 (the distance from the speed change operation shaft 63 is shorter), and is formed to be inclined so as to approach the speed change operation shaft 63 from the start end to the end.

  The cam groove 62a is slidably engaged with a distal end portion of a first arm 63c that is rotatably supported by the vehicle body frame 4 and extends from a horizontal shaft 63b. Then, the second arm 63d fixed to the horizontal shaft 63b is interlocked and connected to an accelerator lever 5a serving as a rotation speed changing means in the engine 5 via a wire 5b or the like.

  In this configuration, when the speed change actuator 60 is rotationally driven so as to increase the moving speed, the sector gear 62 rotates in the direction of arrow C in FIG. In response to this rotation, the first arm 63c moves along the cam groove 62a, and the accelerator lever 5a moves against the return spring means 5c in the direction of arrow J in FIG. Rotate. Therefore, the engine speed automatically increases in proportion to the increase in the moving speed from the idle speed.

  On the other hand, when the speed change actuator 60 is rotationally driven so as to reduce the moving speed, the sector gear 62 rotates in the direction of arrow D in FIG. In response to this rotation, the first arm 63c moves in the opposite direction along the cam groove 62a, and the accelerator lever 5a rotates in the direction of arrow K due to the rotation of the second arm 63d. Therefore, the engine speed automatically decreases in proportion to the reduction in the moving speed, and becomes the idling speed when traveling stops.

  Thus, in this embodiment, the rice transplanter 1 is configured to automatically change the rotational speed of the engine 5 in accordance with the speed change operation in the traveling speed change mission 20. The rice transplanter 1 is also configured to be able to arbitrarily change the rotational speed of the engine 5 by manually turning the accelerator lever 5a.

  Next, the control configuration will be described.

As shown in FIG. 7, the control device 80 includes a first detection means 55, a second detection means 66, a maximum speed setter 77, a moving speed detection means 86, an engine speed detection means 87, and tilting. Detection means 88, steering amount detection means 89, water temperature detection means 90, and oil temperature detection means 91 are connected.
Further, the speed change actuator 60, the display panel 15, the engine speed control means 85, and the brake on / off member 75 are connected to the control device 80.

  The maximum speed setting unit 77 includes a dial or a lever provided in the driving operation unit 10 and is configured to be able to set the maximum moving speed of the rice transplanter 1.

  The moving speed detection means 86 includes a rotation speed sensor that detects the rotation speed of an axle or the like, and is configured to be able to detect the movement speed of the rice transplanter 1 from the detection value of the rotation speed sensor.

  The engine speed detection means 87 includes a speed sensor that detects the speed of the output shaft of the engine 5 and is configured to detect the speed of the engine 5 from the detection value of the speed sensor. .

The tilt detection means 88 includes a tilt sensor (tilt sensor) that detects the tilt angle (tilt) of the traveling machine body 3, and detects the tilt angles of the traveling machine body 3 in the front-rear direction and the left-right direction from the detection value of the tilt sensor. It is configured to be able to.
From the detection result of the tilt detection means 88, it is possible to determine the traveling conditions (flat ground and sloping ground) of the rice transplanter 1, that is, what kind of inclination the rice transplanter 1 is traveling on.

The steering amount detection means 89 includes a steering sensor that detects the steering angle of the steering handle 13, and is configured to detect the steering amount (rotation angle) of the steering handle 13 from the detection value of the steering sensor. Has been.
The steering sensor is composed of a potentiometer, a rotary encoder, or the like disposed near the steering shaft of the steering handle 13.

  The water temperature detection means 90 includes a water temperature sensor that detects the water temperature of the cooling water of the engine 5 and detects the cooling water temperature of the engine 5 from the detection value of the water temperature sensor.

  The oil temperature detecting means 91 is composed of a continuously variable transmission 21 or an oil temperature sensor that detects the oil temperature of the lubricating oil of the engine 5, and detects the temperature of the continuously variable transmission 21 from the detected value of the oil temperature sensor.

The engine speed control means 85 is configured to be able to control the engine speed of the engine 5 by changing the fuel injection amount, the intake air amount, and the like depending on the type of the internal combustion engine.
Since the engine 5 is a diesel engine in the rice transplanter 1 of this embodiment, the engine speed of the engine 5 can be controlled by changing the fuel injection amount by changing the rack position with a solenoid as an actuator. Configured to be able to.
When the engine 5 is a gasoline engine, the motor is driven to open and close the throttle, thereby adjusting and controlling the engine speed of the engine 5.

  The brake on / off member 75 includes an electric motor or cylinder, or a hydraulic cylinder controlled by an electromagnetic valve, and is configured so that the brake mechanism 23 can be switched between a non-operating state and an operating state by its operation. The However, the brake on / off member 75 is provided so that the brake mechanism 23 can be operated by giving priority to the operation of the brake pedal 17 without interfering with the operation of the brake mechanism 23 by the operating member 46.

Next, the maximum speed control mechanism of the rice transplanter 1 will be described.
The maximum speed control mechanism of the rice transplanter 1 is a mechanism that controls the maximum movement speed when the shift pedal 16 is fully depressed (when the amount of depression of the shift pedal 16 is maximum).
The maximum speed control mechanism of the rice transplanter 1 is provided with the above-described maximum speed setter 77.
By setting the predetermined speed with the maximum speed setting unit 77, the maximum moving speed when the shift pedal 16 is depressed to the maximum is limited to the predetermined speed set.
Further, the control device 80 sets the maximum moving speed by the maximum speed setting unit 77 according to the traveling conditions (flat and inclined land) and traveling state of the rice transplanter 1, the temperature of the engine 5 and the continuously variable transmission 21, and the like. The rotational drive of the speed change actuator 60 is controlled so as to be limited to the set value.
Below, control of the maximum speed control mechanism of the rice transplanter 1 is demonstrated.

First, the relationship between the maximum speed control mechanism of the rice transplanter 1 and the travel conditions (flat ground and sloping ground) of the rice transplanter 1 will be described.
As shown in FIG. 7, a maximum speed setting unit 77 is connected to the control device 80, and the maximum moving speed is set by the maximum speed setting unit 77. The control device 80 performs control so that the set moving speed becomes the maximum moving speed when the shift pedal 16 is depressed to the maximum.
The tilt detection means 88 is connected to the control device 80, and the tilt detection means 88 detects the tilt angle of the traveling machine body 3. The control device 80 limits the moving speed of the rice transplanter 1 based on the detection result.

As shown in FIG. 8, when the key switch is turned on, the control device 80 acquires the maximum movement speed set by the maximum speed setting unit 77 and the inclination angle of the traveling machine body 3 from the inclination detection means 88 (S1). Then, the corrected maximum movement speed for the inclination angle is calculated from the set maximum movement speed and the detected inclination angle (S2).
The maximum movement speed when driving on a level place with the maximum speed setter 77 and when traveling on the slope with the set state, the maximum movement speed up to the maximum movement speed corrected according to the slope (tilt angle) When the position is lowered, the posture of the rice transplanter 1 is stabilized and the driver can travel with peace of mind. Therefore, the maximum movement speed when traveling on a slope is corrected so as to be a speed corresponding to the maximum movement speed set by the maximum speed setter 77 (a speed slower than the maximum movement speed set by the maximum speed setter 77). To do.
Specifically, the maximum movement speed with respect to the inclination angle is set in advance by a map or the like, and the maximum movement speed set by the operator using the maximum speed setting unit 77 is the maximum movement speed during horizontal running. The maximum movement speed when traveling is also adjusted so that the maximum movement speed with respect to the inclination angle obtained from the map is reduced at the same rate according to the ratio of the speed limited by the maximum speed setting unit 77 during horizontal traveling. It makes it move speed.
Here, the “maximum moving speed with respect to the tilt angle” refers to the maximum value of the moving speed of the traveling machine body 3 that can stably travel while the rice transplanter 1 is tilted. The map is stored in storage means (ROM) of the control device 80. It is also possible to configure the ratio to be arbitrarily changed.

Then, when the operator depresses the speed change pedal 16 of the driving operation unit 10 to start traveling of the rice transplanter 1, the control device 80 determines the inclination angle of the traveling machine body 3 detected by the tilt detection means 88. Obtain (S3). The control device 80 compares the acquired inclination angle of the traveling machine body 3 with a preset set angle, and determines whether or not the acquired inclination angle of the traveling machine body 3 is equal to or larger than the set angle (S4). ).
Here, the “preset angle” is the maximum value of the inclination angle of the traveling machine body 3 in which the rice transplanter 1 can travel in a stable posture even at the maximum moving speed set by the maximum speed setting unit 77. Say.

  When it is determined that the inclination angle of the traveling machine body 3 by the tilt detection means 88 is not equal to or greater than the set angle (S4-No), that is, even when the maximum moving speed set by the maximum speed setting unit 77 is reached, the rice transplanter 1 is stable. If it is determined that the vehicle is traveling in a posture, the control device 80 continues to acquire the inclination angle of the traveling machine body 3 by the tilt detection means 88 (S3).

  When it is determined that the tilt angle of the traveling machine body 3 by the tilt detection means 88 is equal to or greater than the set angle (S4-Yes), that is, at the maximum moving speed set by the maximum speed setter 77, the rice transplanter 1 is in a stable posture. If it is determined that the vehicle cannot travel, the control device 80 sets the maximum movement speed when the shift pedal 16 is fully depressed to the maximum movement speed (S2) corrected for the calculated inclination angle, that is, The rotational drive of the speed change actuator 60 is limited so that the maximum movement speed is lower than the maximum movement speed set by the maximum speed setter 77 (S5).

When traveling on a horizontal place, the maximum movement speed set by the maximum speed setting unit 77 is limited, and the maximum movement speed is limited (decreased) as the inclination angle increases. Is done. Further, the correction value for the tilt angle may be a different value between the front-rear direction and the left-right direction. That is, the maximum moving speed when the rice transplanter 1 is tilted in the front-rear direction can be set to be faster than the maximum moving speed when the rice transplanter 1 is tilted in the left-right direction.
It is also possible to make the correction value different between the forward and downward slope and the forward slope. That is, it is possible to set the maximum moving speed when the rice transplanter 1 travels on the forward and downward slope to be slower than the maximum movement speed when the rice transplanter 1 travels on the forward and upward slope.

Next, the relationship between the maximum speed control mechanism of the rice transplanter 1 and the traveling state (traveling direction) of the rice transplanter 1 will be described.
As shown in FIG. 7, the steering amount detection means 89 is connected to the control device 80, and the steering amount detection means 89 detects the steering angle of the steering handle 13. The control device 80 detects the steering amount of the steering handle 13 based on the detection result. Here, the steering amount of the steering handle 13 is an amount proportional to the degree of direction change of the rice transplanter 1, and if the steering amount of the steering handle 13 is large, the rice transplanter 1 is greatly changed direction. .

As shown in FIG. 9, when the operator depresses the speed change pedal 16 of the driving operation unit 10 to start traveling of the rice transplanter 1, the control device 80 controls the operation detected by the steering amount detection means 89. The steering angle of the direction handle 13 is acquired (S11). The control device 80 calculates a steering amount of the steering handle 13 by calculating a change in the steering angle of the steering handle 13 every predetermined time from the obtained steering angle of the steering handle 13 (S12). The control device 80 compares the calculated steering amount with a preset set steering amount, and determines whether or not the steering amount of the steering handle 13 is equal to or greater than the set steering amount (S13).
The “predetermined set steering amount” here is a steering amount of the steering handle 13 that can change the direction of the rice transplanter 1 in a stable posture even at the maximum moving speed set by the maximum speed setter 77. The maximum value.

  When it is determined that the calculated steering amount of the steering handle 13 is not equal to or greater than the set steering amount (S13-No), that is, even when the maximum moving speed set by the maximum speed setting unit 77 is reached, the rice transplanter 1 is stabilized. If it is determined that the direction change (normal travel) is possible in the posture, the control device 80 continues to acquire the steering angle of the steering handle 13 by the steering amount detection means 89 (S11).

  When it is determined that the calculated steering amount of the steering handle 13 is equal to or greater than the set steering amount (S13-Yes), that is, the rice transplanter 1 is in a stable orientation at the maximum moving speed set by the maximum speed setting unit 77. If it is determined that the shift cannot be made, the control device 80 rotates the speed change actuator 60 so that the maximum movement speed when the shift pedal 16 is fully depressed is lower than the maximum movement speed set by the maximum speed setter 77. Driving is limited (S14).

  After lowering the maximum moving speed, the control device 80 acquires again the steering angle of the steering handle 13 detected by the steering amount detecting means 89 (S15), and calculates the steering amount of the steering handle 13 in the same manner as described above. In step S16, the calculated steering amount of the steering handle 13 is compared with a preset set steering amount to determine whether the calculated steering amount of the steering handle 13 exceeds the set steering amount. (S17).

  When it is determined that the calculated steering amount of the steering handle 13 is equal to or greater than the set steering amount (S17-Yes), that is, when it is subsequently determined that the rice transplanter 1 cannot change direction in a stable posture, the control device 80 Subsequently, the rotational drive of the speed change actuator 60 is limited so that the maximum movement speed when the shift pedal 16 is depressed to the maximum is lower than the maximum movement speed set by the maximum speed setting unit 77 (S14).

When it is determined that the calculated steering amount of the steering handle 13 is not equal to or greater than the set steering amount (S17-No), that is, even when the maximum moving speed set by the maximum speed setting unit 77 is used, the rice transplanter 1 is in a stable posture. When it is determined that the direction change (normal travel) is possible, the control device 80 switches the limit of the maximum movement speed when the shift pedal 16 is operated to the maximum to the limit by the maximum speed setting unit 77, and the shift actuator The restriction on the rotational drive of 60 is released (S18).
At this time, the maximum speed setting unit 77 also sets the maximum moving speed during the above-mentioned straight traveling / tilting, and the control device 80 performs the maximum movement during straight traveling and during tilting according to the setting of the maximum speed setting unit 77. Limit the speed and control the maximum speed to be slower when changing direction. In this case, the correction value is further added. It is also possible to set so that the maximum speed becomes smaller (slower) as the turning angle becomes larger when the direction is changed.

Next, the relationship between the maximum speed control mechanism of the rice transplanter 1 and the temperatures of the engine 5 and the continuously variable transmission 21 will be described.
As shown in FIG. 7, the water temperature detection means 90 is connected to the control device 80, and the water temperature detection means 90 detects the water temperature of the cooling water of the engine 5. Control device 80 detects the temperature of engine 5 based on the detection result.
The oil temperature detecting means 91 is connected to the control device 80, and the oil temperature detecting means 91 detects the oil temperature of the continuously variable transmission 21. The control device 80 detects the temperature of the continuously variable transmission 21 based on the detection result.

As shown in FIG. 10, when the operator depresses the speed change pedal 16 of the driving operation unit 10 to start traveling of the rice transplanter 1, the control device 80 detects the engine 5 detected by the water temperature detecting means 90. And the lubricating oil temperature of the continuously variable transmission 21 or the engine 5 detected by the oil temperature detecting means 91 are acquired (S21). The control device 80 compares the acquired coolant temperature of the engine 5 and the lubricating oil temperature of the continuously variable transmission 21 or the engine 5 with a preset set temperature, and acquires the acquired coolant temperature of the engine 5, Alternatively, it is determined whether one or both of the continuously variable transmission 21 and the lubricating oil temperature of the engine 5 are equal to or higher than the set temperature (S22).
Here, “preset temperature” means that the coolant temperature of the engine 5 is lower than the coolant temperature when the engine 5 is overloaded (overheated), the continuously variable transmission 21 or the engine 5 The lubricating oil temperature refers to a temperature lower than the lubricating oil temperature when the continuously variable transmission 21 is overloaded (overheated).

  When it is determined that the acquired coolant temperature of the engine 5 and the continuously variable transmission 21 or the lubricating oil temperature of the engine 5 are not equal to or higher than the set temperature (S22-No), that is, the engine 5 and the continuously variable transmission 21 are excessive. If it is determined that the load is not overheated, the control device 80 continues to acquire the coolant temperature of the engine 5 and the continuously variable transmission 21 or the lubricating oil temperature of the engine 5 by the water temperature detecting means 90 and the oil temperature detecting means 91. (S21).

  When it is determined that the obtained coolant temperature of the engine 5 and / or the temperature of either the continuously variable transmission 21 or the lubricating oil temperature of the engine 5 are equal to or higher than the set temperature (S22-Yes), That is, when it is determined that one or both of the engine 5 and the continuously variable transmission 21 are overloaded (overheat), the control device 80 determines that the maximum moving speed when the shift pedal 16 is fully depressed is the maximum speed setting unit 77. The rotational drive of the speed change actuator 60 is controlled so as to be lower than the maximum moving speed set by (S23).

  After lowering the maximum moving speed, the control device 80 again acquires the coolant temperature of the engine 5 and the continuously variable transmission 21 or the lubricating oil temperature of the engine 5 detected by the water temperature detecting means 90 and the oil temperature detecting means 91. (S24), similarly to the above, the obtained coolant temperature of the engine 5, the lubricating oil temperature of the continuously variable transmission 21 or the engine 5, and the preset set temperature are compared with each other to obtain the obtained engine 5 It is determined whether or not one of the cooling water temperature, the continuously variable transmission 21 or the lubricating oil temperature of the engine 5 is equal to or higher than the set temperature (S25).

  When it is determined that the obtained coolant temperature of the engine 5 and / or the temperature of either the continuously variable transmission 21 or the lubricating oil temperature of the engine 5 is equal to or higher than the set temperature (S25-Yes), That is, when it is determined that one or both of the engine 5 and the continuously variable transmission 21 are overloaded (overheat), the control device 80 causes the display panel 15 to display either the engine 5 or the continuously variable transmission 21 or An indication that both are overloaded (overheat) is displayed (S26).

When it is determined that the obtained coolant temperature of the engine 5 and the continuously variable transmission 21 or the lubricating oil temperature of the engine 5 are not equal to or higher than the set temperature (S25-No), that is, the engine 5 and the continuously variable transmission 21 are excessive. If it is determined that the load (overheating) is not detected, the control device 80 switches the limit of the maximum movement speed when the shift pedal 16 is operated to the maximum to the limit by the maximum speed setter 77 and drives the shift actuator 60 to rotate. Is performed by normal control (S27).
At this time, in the maximum speed setter 77, the maximum movement speed is limited according to the straight traveling, the inclination, and the turning angle.

As described above, the maximum speed control mechanism of the rice transplanter 1 is
Shift control of the continuously variable transmission 21 is performed based on the operation amount of the traveling machine body 3 on which the engine 5 is mounted, the continuously variable transmission 21, the transmission pedal 16 (transmission operation tool), and the transmission pedal 16 (transmission operation tool). In the rice transplanter 1 provided with the speed change actuator 60,
A maximum speed setting unit 77 is provided for limiting the maximum movement speed when the shift pedal 16 (transmission operation tool) is operated to the maximum, and the maximum movement speed can be limited by traveling on the road or tilting the traveling machine body. .
By configuring in this way, the maximum speed value can be changed according to the driver's preference, traveling conditions (flat and inclined ground), etc., when an unskilled pilot works, When the driving condition is bad, even if the shifting operation tool is operated to the maximum, it does not run at a high speed, so that the maneuverability and the driving performance can be improved.

The maximum speed control mechanism of rice transplanter 1 is
Tilt detection means 88 (tilt sensor) for detecting the tilt of the traveling machine body 3 is provided, and when the detection result of the tilt detection means 88 (tilt sensor) is a predetermined value or more, the detection result of the tilt detection means 88 (tilt sensor) is The maximum moving speed is configured to be lower than when it is less than a predetermined value.
By configuring in this way, when the traveling machine body 3 tilts back and forth or left and right, the maximum moving speed automatically decreases. it can.

Furthermore, the maximum speed control mechanism of rice transplanter 1 is
The steering amount detection means 89 (steering sensor) of the steering handle 13 is provided, and when the detection result of the steering amount detection means 89 (steering sensor) is a predetermined value or more, the detection result of the steering amount detection means 89 (steering sensor) is The maximum moving speed is configured to be lower than when it is less than a predetermined value.
With this configuration, when the steering handle 13 is rotated to largely change the direction of the traveling vehicle body 3, the maximum moving speed is automatically lowered, so that the moving speed is not affected even if a speed change operation is mistakenly performed. It is possible to prevent the speed from being increased appropriately.

Furthermore, the maximum speed control mechanism of the rice transplanter 1 is
When the detection result of one or both of the water temperature detection means 90 (water temperature sensor) of the engine 5 and the oil temperature detection means 91 (oil temperature sensor) of the continuously variable transmission 21 is equal to or greater than a predetermined value, the detection result is predetermined. The maximum moving speed is lower than when the value is less than the value.
With this configuration, when the temperature of the engine 5 or the continuously variable transmission 21 becomes high during the planting operation, the set value of the maximum movement speed is automatically lowered, so that the engine 5 or the continuously variable transmission The trouble that the transmission 21 is overloaded (overheated) can be prevented.

DESCRIPTION OF SYMBOLS 1 Rice transplanter 3 Traveling machine body 5 Engine 13 Steering handle 16 Shift pedal 21 Infinitely variable transmission 60 Shifting actuator 80 Control device 89 Steering amount detection means (steering sensor)
90 Water temperature detection means (water temperature sensor)
91 Oil temperature detection means (oil temperature sensor)

Claims (4)

In a work vehicle comprising: a traveling machine body on which an engine is mounted; a continuously variable transmission; a transmission operation tool; and an actuator that controls the transmission of the continuously variable transmission based on an operation amount of the transmission operation tool.
A maximum speed control mechanism for a work vehicle provided with a maximum speed setting device for limiting a maximum movement speed when the shift operation tool is operated to the maximum, and configured to be able to limit the maximum movement speed by traveling on the road or tilting the traveling machine body.   A tilt sensor for detecting the tilt of the traveling machine body, and when the detection result of the tilt sensor is equal to or greater than a predetermined value, the maximum movement speed is made lower than when the detection result of the tilt sensor is less than the predetermined value. The maximum speed control mechanism of the work vehicle according to claim 1 configured.   A steering sensor for a steering wheel is provided, and when the detection result of the steering sensor is greater than or equal to a predetermined value, the maximum movement speed is lower than when the detection result of the steering sensor is less than a predetermined value. The maximum speed control mechanism of the work vehicle as described in 1.   When the detection result of one or both of the water temperature sensor of the engine and the oil temperature sensor of the continuously variable transmission is greater than or equal to a predetermined value, the maximum moving speed is lower than when the detection result is less than the predetermined value. The maximum speed control mechanism of the work vehicle according to claim 1 configured as described above.

Images