JP7453006B2 - work vehicle - Google Patents

Description

The present invention relates to a work vehicle that includes a control section that decelerates a traveling machine body according to an inclination angle of the traveling machine body.

A traveling aircraft having a traveling HST that travels and changes speed in a stepless manner, a main shift operation lever that performs a stepless speed change operation of the traveling aircraft, an inclination sensor that detects a tilt angle of the traveling aircraft in the left and right direction, and a control unit. The controller is configured to decelerate the traveling aircraft to a predetermined safe speed when it is detected that the horizontal inclination angle of the traveling aircraft is equal to or greater than a predetermined angle. A work vehicle described in Patent Document 1 is conventionally known.

According to the above-mentioned document, when it is detected that the traveling machine has tilted more than a predetermined level, the speed can be reduced to a predetermined safe speed to improve safety when traveling on a sloped surface. If the traveling machine is traveling on a slope at a relatively fast speed, the traveling machine may be suddenly decelerated at an unexpected timing, which may affect operability and safety, and may cause the machine to move more than necessary. There was a problem in that work efficiency could be lowered more than necessary due to deceleration.

Japanese Patent Application Publication No. 2002-340182

The present invention provides a work vehicle capable of performing automatic deceleration control that decelerates the traveling body when the traveling body tilts beyond a preset inclination angle, and improves the safety and work efficiency of the traveling body while working on a slope. Our goal is to provide a work vehicle that can achieve both of these goals.

In order to solve the above problems, the present invention provides a traveling aircraft, an operating tool that performs a gear change operation of the traveling aircraft, an operating position detection sensor that detects the operating position of the operating tool, and a position detected by the operating position detection sensor. a transmission device configured to change the speed of the traveling aircraft in multiple stages based on the operating position of the operating tool; a tilt sensor that detects a tilt angle of the traveling aircraft in the left-right direction; and an engine of the traveling aircraft. a traveling clutch that connects and disconnects the power transmitted to the drive wheels; a brake device that brakes the traveling aircraft; an actuator that switches the transmission of the transmission; Another actuator for switching between a forward traveling state and a backward traveling state, a detection result by the operation position detection sensor and a detection result by the tilt sensor are input, and the first actuator changes the speed of the transmission. and a control unit that controls switching between forward and backward movement and stopping of the traveling aircraft by the other actuator, and controls whether or not the braking is applied to the traveling aircraft by the brake device, the controller comprising: Control for automatically shifting the transmission in a deceleration direction by the first actuator on the condition that it is detected that the horizontal inclination angle of the traveling aircraft is equal to or greater than a preset first inclination angle. If it is detected that the inclination angle of the traveling aircraft in the left-right direction is greater than or equal to a second inclination angle that is set to be larger than the first inclination angle, the braking device causes the traveling aircraft to The vehicle is characterized in that it is configured to perform control to automatically stop the traveling aircraft by braking and switching the transmission to a neutral state using the other actuator.

The control unit automatically stops the traveling aircraft regardless of the operating position of the operating tool when it is detected that the horizontal inclination angle of the traveling aircraft is equal to or greater than the second inclination angle. , the speed change state of the transmission device and the operating position of the operating tool are brought into a mismatched state, and then the speed changing state of the transmission device and the operating position of the operating tool are brought into agreement by an operator's operation of the operating tool; When detected , the control for automatically stopping the traveling aircraft may be canceled .

The control unit may be arranged such that, while executing the control for automatically shifting the transmission in a deceleration direction, the traveling aircraft is located on a slope, and the inclination angle in the left-right direction is greater than or equal to the second inclination angle. If it is detected that the traveling aircraft is in the above-mentioned state, the control for automatically stopping the traveling aircraft is executed, and thereafter, the inclination angle of the traveling aircraft in the left-right direction is less than the second inclination angle by the operator's operation. When the state recovers to the above state, the control for automatically shifting the transmission in the deceleration direction may be resumed.

The control unit is configured to shift the transmission in a deceleration direction when the horizontal inclination angle of the traveling aircraft becomes equal to or greater than the first preset inclination angle, and By configuring the system to automatically stop the traveling aircraft when the inclination angle is 2 or more, the transmission automatically decelerates in stages as the horizontal inclination of the traveling aircraft increases. Since automatic stopping is performed in stages, it is possible to achieve both safety when driving on slopes and work efficiency.

Further, the control unit is configured to be able to automatically stop the traveling aircraft regardless of the operating position of the operating tool, and the control unit is configured to control the speed change state of the transmission device and the operating tool. If it is detected that the operation positions of It is possible to efficiently prevent the situation where the vehicle starts traveling at a timing not intended by the operator.

Note that when the control unit detects that the horizontal tilt angle of the traveling aircraft has recovered from a state equal to or greater than the second tilt angle after the traveling aircraft has automatically stopped due to the automatic deceleration control. According to the configuration in which automatic deceleration of the transmission device is restarted by the automatic deceleration control, until the traveling aircraft comes out of the state tilted by a second tilt angle or more, Since there is no restriction on the transmission, it is possible to smoothly move the traveling aircraft away from a steeply sloped place.

FIG. 1 is a side view of a tractor to which the present invention is applied. FIG. 1 is a front view of a tractor to which the present invention is applied. FIG. 3 is a front view of main parts showing the control section. It is a figure showing an operation panel. It is a block diagram of a control part. FIG. 3 is a table showing a control pattern for slope running control. FIG. 3 is a flow diagram showing slope running control.

1 and 2 are a side view and a front view of a tractor to which the present invention is applied, FIG. 3 is a front view of main parts showing a control section, and FIG. 4 is a diagram showing an operation panel. . This tractor includes a body frame 3 supported by a pair of left and right front wheels 1, 1 and rear wheels 2, 2, and a bonnet 4 that covers the upper side of an engine (not shown) installed on the front side of the body frame 3. , and a cabin 6 which is provided with a control section installed behind the hood 4 and into which an operator gets in and performs operations, etc. (see FIG. 1). Further, a working machine 10 such as a rotary tiller is connected to the rear of the traveling body 7 via an elevating link 5 so as to be movable up and down.

The control section includes a seat 8 on which an operator is seated, a steering handle 9 that is a steering operation tool disposed in front of the seat 8, and a display panel 11 disposed in front of the steering handle 9. A PTO gear shift lever 12 disposed below the steering handle 9, an auxiliary gear shift lever 13 disposed on one of the left and right sides (left in the illustrated example) of the seat 8, and a sub-shift lever 13 disposed on the left and right sides of the seat 8 (left in the illustrated example); In the example, there is an operation panel 14 arranged on the right side), a floor step 16 which is a floor provided between the seat 8 and the steering handle 9, and a floor step 16 arranged on the side of the floor step 16, which is the floor surface of the traveling aircraft 7. The brake pedal 17 is provided with a brake pedal 17 for operating a braking operation (see FIG. 2).

The auxiliary gear shift lever 13 is configured to be able to switch at least between forward travel, a road travel state suitable for road travel, and a work travel state suitable for work travel, via a transmission (transmission device). ing. In the illustrated example, the speed can be switched to three stages: high speed (H), medium speed (M) suitable for road driving, and low speed (L) suitable for work driving.

The operation panel 14 is arranged side by side on the left and right inner side of the main shift lever 18, which is configured to be able to operate the main shift by being swung in the front and back direction, and is arranged to operate the work machine up and down. A working machine lift lever 19, a travel mode changeover switch 21 disposed in front of the main shift lever 18, and a PTO switch 23 are provided.

The main shift lever 18 is configured to be capable of operating a travel gear change via a transmission device that changes the speed of the travel aircraft in stages. At this time, the transmission is capable of stepped shifting in multiple stages (in other words, can be set to multiple gears S) by controlling an HST (hydraulic continuously variable transmission) by a control unit 50 described later. It is configured.

Specifically, the main shift lever 18 is provided with a main shift lever potentiometer (operation position detection sensor) 22 that detects the longitudinal swing (operation) position, and the transmission device The main shift lever 18 is shifted in multiple stages (in the illustrated example, a total of 8 stages from 1st to 8th speed) depending on the operating position (set gear S1) of the main gear shift lever 18 (setting the gear S). It is configured so that it can be done.

The working machine lifting lever 19 can lift and lower the working machine at the rear of the traveling machine body 7 by telescopically operating a lifting cylinder (not shown) at the rear of the traveling machine body 7. According to this configuration, the rotary tiller connected to the rear part of the traveling machine body 7 can be operated from a non-working height to a working height for tilling a field, and the rotary tiller at the working height can be operated from a non-working height to a working height for tilling a field. By adjusting the lifting position, the plowing depth can be changed depending on the purpose and field conditions.

The driving mode changeover switch 21 is configured to be able to switch to an inclined driving mode in which slope driving control is executed by a control section 50, which will be described later. Details of the slope value traveling control will be described later.

Next, based on FIGS. 5 to 7, slope value traveling control by the control section will be described. FIG. 5 is a block diagram of the control unit, and FIG. 6 is a table showing a control pattern for slope running control.

On the input side of the control unit 50, as shown in FIG. A left-right tilt sensor (tilt sensor) 31 that detects the tilt angle of the aircraft body 7 in the left-right direction; ) 22 are connected.

On the output side of the control unit 50, there is a main shift solenoid 32, which is an actuator that is configured to change the speed of the transmission in stages by controlling the swash plate of the HST, and A forward/reverse solenoid 33, which is an actuator for switching forward, backward, and stopping, a brake solenoid 34, which operates a brake, the travel clutch 36 (an actuator that operates the clutch intermittently), and a notification means 37, which will be described later, are connected. has been done.

When the control unit 50 detects that the horizontal inclination angle θ of the traveling aircraft 7 has become larger than a predetermined deceleration inclination angle (first inclination angle) α by the left-right inclination sensor 31. In addition to automatically decelerating the traveling body 7 (transmission device) via the main shift solenoid 32, a stop slope is set such that the horizontal tilt angle θ of the traveling body 7 is larger than the deceleration tilt angle α. When it is detected that the angle (second inclination angle) has become larger than β, slope running control configured to automatically stop the traveling aircraft 7 is configured to be executable (Fig. (See 2nd prize).

To be more specific, as shown in FIG. 6, when the slope running control automatically decelerates and switches the traveling body (transmission), the speed change of the transmission is performed via the main shift solenoid 32. The set gear S1 is configured to be decelerated by a predetermined number of gears (in the illustrated example, two stages) from the gear gear corresponding to the operating position of the main gear shift lever 18.

Incidentally, the transmission device uses the main shift solenoid 32 to forcibly decelerate (downshift) two steps from the gear position at which the main shift lever 18 is operated, regardless of the operating position of the main shift lever 18. It is configured. That is, automatic deceleration switching of the traveling aircraft 7 by the slope traveling control is performed when the gear shift state (gear S) of the traveling aircraft (transmission device) and the gear indicated by the operating position of the main gear shift lever 18 do not match. (See Figure 6).

According to the slope running control with this configuration, when the traveling body 7 is traveling on a slope and the left and right direction of the traveling body 7 is tilted by a predetermined angle or more, the traveling body 7 is automatically controlled. While ensuring safety by (forced) deceleration, it is possible to prevent the traveling body 7 from being decelerated more than necessary and greatly deteriorating work efficiency. Further, it is also possible to prevent a situation in which the traveling body 7 is suddenly decelerated all at once when traveling on a slope, thereby interfering with the operator's steering operation.

Further, the control unit 50 is configured such that, in deceleration via the main shift solenoid 32, the stepped deceleration by the transmission is not performed below a predetermined lower limit gear position Sl (second speed in the illustrated example). (See Figure 5). Incidentally, the deceleration width by the main shift solenoid 32 and the lower limit shift stage Sl are determined by the working height of the rotary tiller, in other words, the tilling depth (shallow plowing (high), standard plowing (standard), deep plowing (low) )) The settings can be changed according to (see FIG. 6).

According to this configuration, when the traveling body 7 is originally traveling in a suitably decelerated state, deceleration of the traveling body 7 by the slope traveling control is not executed, so that work efficiency is required. This can prevent the situation from getting worse.

Further, when the horizontal inclination of the traveling body 7 becomes larger than the stop inclination angle β, the control unit 50 disengages the traveling clutch 36 and controls the forward/reverse solenoid 33 and the brake solenoid 34. By braking the traveling aircraft 7, the traveling aircraft 7 can be automatically stopped. At this time, the control unit 50 may also be configured to automatically stop the engine.

Note that, when the traveling body 7 is decelerated by the slope traveling control, the left and right inclination of the traveling body 7 becomes smaller than the deceleration inclination angle α, and the main shift lever 18 is operated in the deceleration direction, so that the operation position of the main shift operating lever 18 (set gear S1) matches the gear S of the transmission that has been decelerated by the main shift solenoid 32. , the forced deceleration caused by the slope running control is canceled.

According to this configuration, when the traveling aircraft is automatically decelerated by the slope traveling control, a situation where the deceleration of the traveling aircraft is canceled and the speed suddenly increases at a timing unintended by the operator is reliably prevented. be able to.

Incidentally, the control unit 50 can notify the operator of a state in which the traveling aircraft automatically decelerates or stops due to the slope running control, or a state in which these are canceled, to the operator using the notification means 36. It is configured as follows. Specifically, as the notification means 36, a notification buzzer, a notification lamp provided on the display panel 11 side, a monitor (not shown) provided separately on the control section side, etc. are used. Not limited.

FIG. 7 is a flowchart showing slope running control. When the slope running control process is started, the process advances to step S1. In step S1, it is confirmed by the traveling mode changeover switch whether the traveling body has been switched to slope mode, and if it is detected that it has been switched to slope mode, the process proceeds to step S2. Note that if it is not detected in step S1 that the mode has been switched to the slope mode, then the process returns.

At this time, in step S1, instead of whether or not the driving mode changeover switch 21 switches to slope mode, the operation position of the sub-shift lever 13, the operation status of the PTO lever 12 (switch), and the control mode setting are determined. The switch 24 or the like may be used to determine whether or not the traveling body 7 is in a state where it is traveling for work on a field including a slope.

In step S2, it is confirmed whether the horizontal tilt angle θ of the traveling body 7 detected by the horizontal tilt sensor 31 is equal to or greater than the preset stop tilt angle β, and the horizontal tilt angle θ of the traveling body 7 is If it is not detected that the inclination angle in the direction is equal to or greater than the stop inclination angle β, the process proceeds to step S3.

In step S3, ON/OFF of an emergency stop flag, which will be described later, is confirmed, and if the OFF state of the emergency stop flag is detected, the process proceeds to step S4.

In step S4, it is confirmed whether the horizontal inclination angle θ of the traveling aircraft 7 detected by the lateral inclination sensor 31 is equal to or greater than the deceleration inclination angle α and smaller than the stop inclination angle β, and the traveling aircraft If it is detected that the inclination angle θ is greater than or equal to the deceleration inclination angle α and smaller than the stop inclination angle β, the process proceeds to step S5.

In step S5, ON/OFF of a deceleration control flag, which will be described later, is confirmed, and if the OFF state of the deceleration control flag is detected, the process proceeds to step S6. In step S6, the deceleration control flag is set to ON, and then the process proceeds to step S7.

Note that if the ON state of the deceleration control flag is detected in step S5, the process directly proceeds to step S7.

In step S7, it is detected whether the operating position (set gear S1) of the main shift operating lever 18 is in the range of 2nd speed or higher and 4th gear or lower, and the set gear S1 of the main shift lever 18 is detected. If the speed is not in the range of 2nd speed or higher and 4th speed or lower, the process advances to step S8.

In step S8, it is detected whether the operating position (set gear S1) of the main shift operating lever 18 is the 5th gear or higher, and it is determined whether the set gear S1 of the main shift lever 18 is the 5th gear or higher. If detected, the process advances to step S9.

In step S9, the gear S of the transmission is shifted (downshifted) from the operating position of the main shift lever 18 (set gear S1) to a two-stage deceleration direction via the main shift solenoid 32, and then the do. At this time, the operating position of the main shift lever 18 is not operated, so the gear S of the downshifted transmission and the operating position of the main shift lever 18 (set gear S1) become inconsistent.

Further, in step S8, if it is not detected that the set gear stage S1 of the main shift lever 18 is 5th speed or higher, then the process returns.

If it is detected in step S7 that the set gear position S1 of the main shift lever 18 is within the range of 2nd speed or higher and 4th speed or lower, the process proceeds to step S10. In step S10, the gear S of the transmission is shifted to second speed via the main shift solenoid 32, and then the process returns.

That is, in the slope running control, when the left-right tilt sensor 31 detects that the left-right tilt angle θ of the traveling aircraft 7 is greater than or equal to the deceleration inclination angle α and less than or equal to the stop inclination angle β, The set gear S of the transmission is automatically downshifted by two steps from the operating position of the main shift lever 18 (set gear S1), but the set gear S of the transmission does not become lower than 2nd speed. It is configured as follows.

Further, in step S4, if it is not detected that the inclination angle θ of the traveling body 7 is within the range that is greater than or equal to the deceleration inclination angle α and smaller than the stop inclination angle β, the process proceeds to step S11. In step S11, ON/OFF of the deceleration control flag is confirmed, and if the ON state of the deceleration control flag is detected, the process proceeds to step S12.

In step S12, it is confirmed whether or not the set gear S1 indicated by the operation position of the main shift lever 18 detected by the main shift lever potentiometer 22 matches the gear S of the transmission device. If it is detected that the set gear S1 indicated by the operation position of the gear change lever 18 matches the gear S of the transmission, the process advances to step S13. In step S13, the deceleration control flag is set to OFF, and then the process returns.

Note that in step S12, if the set gear S1 indicated by the operation position of the main shift lever 18 does not match the gear S of the transmission, and if in step S11, the deceleration control flag is in the OFF state. If detected, then return.

That is, in the slope running control, after the transmission is automatically decelerated by the main shift solenoid 32, the left-right tilt angle θ of the traveling body 7 becomes smaller than the deceleration tilt angle α, and the shift When it is detected that the gear S of the device matches the operation position S1 of the main shift lever 18, automatic deceleration switching of the transmission by the slope running control is canceled (the deceleration control flag is turned OFF). set).

Further, in step S2, if it is detected that the horizontal inclination angle of the traveling body 7 is equal to or greater than the stop inclination angle β, the process proceeds to step S14. In step S14, ON/OFF of the emergency stop flag is confirmed, and if the OFF state of the emergency stop flag is detected, the process proceeds to step S15.

In step S15, the traveling body 7 is stopped traveling using the brake solenoid 34, the traveling clutch 36, etc., and the transmission device (main gear shift lever 18) is operated to the neutral state by the forward/reverse solenoid 33, and in an emergency Set the stop flag to ON, then return.

Note that if the ON state of the emergency stop flag is detected in step S14, the process advances to step S16. In step S16, the gear position of the transmission device is shifted according to the operating position of the main shift lever 18, and then the process returns.

That is, in the slope traveling control, when the left-right tilt sensor 31 detects that the horizontal tilt angle θ of the traveling body 7 has become larger than the stop tilt angle β, the traveling body 7 automatically is configured to be stopped. Thereby, together with the notification means 37, it is possible to reliably notify the operator that the inclination angle of the traveling body in the left-right direction is large.

Further, when the traveling aircraft is automatically stopped, the operation position (set gear S1) of the main gear shift lever 18 is operated to the neutral position, so that the traveling aircraft Depending on the operating position, the gear shift operation becomes possible. Therefore, the operator can smoothly resume the operation of escaping from the slope after the traveling body 7 is automatically stopped by the slope travel control.

Incidentally, the slope running control is configured such that the traveling aircraft body 7 automatically stops without changing the operation position of the main shift lever 18, and the transmission is automatically shifted in the deceleration direction. It may be configured such that running can be resumed based on the main shift lever 18 on the condition that the gear position S1 of the transmission device and the operation position of the main shift lever 18 match.

Further, if it is detected in step S3 that the emergency stop flag is in the ON state, the process advances to step S17. In step S17, the emergency stop flag is set to OFF, and then the process returns.

That is, in the slope running control, after the traveling body 7 has automatically stopped, when the horizontal tilt angle θ of the traveling body 7 is recovered to be smaller than the stop tilt angle β, the speed change is performed. The control is configured such that the device is automatically slowed down again.

7 Traveling aircraft 18 Main gear shift lever (operating tool)
22 Main gear shift lever potentiometer (operation position detection sensor)
31 Left and right tilt sensor (tilt sensor)
32 Main shift solenoid (actuator)
33 Forward and backward solenoid (actuator)
36 Travel clutch 37 Brake solenoid (brake device)
50 Control section

Claims (2)

A traveling aircraft,
an operating tool for changing the speed of the traveling aircraft;
an operation position detection sensor that detects the operation position of the operation tool;
a transmission device configured to be able to shift the traveling aircraft in multiple stages based on the operating position of the operating tool detected by the operating position detection sensor;
a tilt sensor that detects a tilt angle of the traveling aircraft in the left-right direction;
a traveling clutch that connects and disconnects power transmitted from the engine of the traveling aircraft to the drive wheels;
a brake device that brakes the traveling aircraft;
an actuator for changing gears of the transmission;
another actuator that switches the transmission between a neutral state, a state in which the traveling aircraft travels forward, and a state in which the traveling aircraft travels backward;
A detection result by the operation position detection sensor and a detection result by the tilt sensor are input, the one actuator controls the speed change of the transmission, and the other actuator switches the traveling aircraft between forward and backward movement and stopping. and a control unit that controls whether or not the traveling aircraft is braked by the brake device ,
The control unit includes:
Control for automatically shifting the transmission in a deceleration direction by the first actuator on the condition that it is detected that the horizontal inclination angle of the traveling aircraft is equal to or greater than a preset first inclination angle. Run
If it is detected that the inclination angle of the traveling aircraft in the left-right direction is equal to or greater than a second inclination angle that is set to be larger than the first inclination angle, braking the traveling aircraft by the brake device, and executing control to automatically stop the traveling aircraft by switching the transmission to a neutral state by the other actuator;
It is configured as follows,
The control unit includes:
While executing the control for automatically shifting the transmission in a deceleration direction, the traveling aircraft is located on a slope, and its horizontal slope angle is equal to or greater than the second slope angle. If this is detected, executing the control to automatically stop the traveling aircraft ,
Thereafter, when the horizontal inclination angle of the traveling aircraft recovers to a state less than the second inclination angle due to an operator's operation, restarting execution of the control for automatically shifting the transmission in the deceleration direction;
A work vehicle configured as such. The control unit includes:
If it is detected that the horizontal inclination angle of the traveling aircraft is equal to or greater than the second inclination angle, the traveling aircraft is automatically stopped regardless of the operating position of the operating tool, and the transmission is adjusted. The speed change state and the operating position of the operating tool are in a mismatched state,
After that, if it is detected that the shift state of the transmission device and the operating position of the operating tool match due to the operator's operation of the operating tool, canceling the control that automatically stops the traveling aircraft;
The work vehicle according to claim 1, configured as follows.

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