JP3982106B2 - Tread changing device for work vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a configuration of a tread changing device for a work vehicle such as an agricultural tractor, a riding management machine, or an aerial work vehicle.
[0002]
[Background Art and Problems to be Solved by the Invention]
Conventionally, a tractor or the like that changes a tread by expansion and contraction of a piston such as a hydraulic cylinder is known.
However, in these conventional work vehicles, if the work is finished or interrupted with the tread changed, the next time the vehicle is started, the operator forgets that the tread has been changed or cannot recognize it, and arbitrarily There was a problem that the steering operation could not be performed, or the both sides were damaged due to contact with obstacles on the side of traveling.
[0003]
[Means for Solving the Problems]
In view of the above problems, the present invention is configured as follows in a tread changing device for a work vehicle.
That is, an actuator 3 for changing the tread of the front wheel 1 or the rear wheel 2 of the vehicle and a sensor 4 for detecting the tread are provided, and the tread of the front wheel 1 or the rear wheel 2 is changed when the vehicle engine is started. A tread changing device for a work vehicle is provided, which includes means 5a, 5b for notifying by voice or display when it is detected.
[0004]
Further, an actuator 3 for changing the tread of the front wheel 1 or the rear wheel 2 of the vehicle and a sensor 4 for detecting the tread are provided, and the tread of the front wheel 1 or the rear wheel 2 is changed when the vehicle engine is started. When it is detected that there is a tread change device for a work vehicle, the control device 6 is provided to temporarily check the start of the vehicle.
[0005]
【The invention's effect】
Since the tread changing device for a work vehicle according to claim 1 configured as described above is configured to notify by voice or display that the tread of the front wheel or the rear wheel is in a changed state when the engine of the vehicle is started. Thus, it is possible to prevent problems such as traveling without being noticed by the operator and contacting an obstacle on the side of the vehicle or causing an obstacle to the steering operation.
[0006]
Further, as described in claim 2, if the tread is changed when the vehicle engine is started, the vehicle can be prevented from starting. This problem can be prevented more reliably.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to a tread changing device for an agricultural tractor (hereinafter, tractor 10) which is a work vehicle.
As shown in FIGS. 3 and 4, the tractor 10 includes an engine 12 provided in a hood 11 at the front of the vehicle body, a clutch housing that houses a main clutch at the rear of the engine 12, and a mission that houses a gear-type transmission. The case 13 is integrally connected. A rear axle case 14 capable of changing the tread is provided at both left and right ends of the transmission case 13, and a rear wheel 2 is provided at an end of the case 14.
[0008]
Further, a front axle case is provided below the engine 12 so as to be able to roll around a front and rear axis, and a front wheel 1 is provided to be steerable at both side ends.
The area around the cockpit 12 of the tractor 10 will be described.
The rear panel of the bonnet 11 is provided with an alarm buzzer 5a serving as a notification means and a meter panel 15 provided with a liquid crystal monitor 5b. A steering handle 16 is provided behind the meter panel 15 so as to steer the front wheel 1. It has become. A shift lever 18 for switching the transmission, a working machine lifting lever 19 and the like are provided on the side of the cockpit 17 so as to protrude, and a potentiometer 20 for detecting the operation position is provided at the rotating base of the working machine lifting lever 19. Is provided. Further, various setting devices such as a tread change on / off switch 21 and a tread width setting device 22 which will be described later are provided in the vicinity of these lever guides, and these setting signals are sent to the controller 23 which is a control unit below the cockpit 17. It is configured to transmit.
[0009]
A cylinder case 26 having a hydraulic cylinder 25 for raising and lowering the work implement is provided at the top of the mission case 13. Then, by extending and retracting the piston of the cylinder 25, the lift arm 27 supported on the left and right of the case 26 is turned up and down, and the working machine connected thereto is moved up and down. Further, a potentiometer type lift arm angle sensor 28 for detecting the height of the work implement is provided on one side of the lift arm 27, and the detection position of the potentiometer 20 of the work implement lift lever 19 and the rotation of the lift arm 27 are provided. The controller 23 is configured to switch the switching control valve for raising or lowering the work machine in the hydraulic circuit so that the movement setting position matches.
[0010]
In the illustrated example, the rotary work machine 35 is connected.
The tread changing device will be described with reference to FIG.
The rear axle case 14 includes a rear wheel differential mechanism 36 at the center of the left and right sides, and engages a wheel support case 37 at both the left and right ends, and protrudes from the rear wheel differential mechanism 36 to the left and right. The drive shafts 38 and 38 are also supported by spline fitting the tip portions so that the left and right can be expanded and contracted. Further, hydraulic cylinders 3 and 3 as tread changing actuators are provided at the front portions of the left and right rear axle cases 14, and piston tip portions of the cylinders 3L and 3R are connected to the wheel support cases 37 and 37, respectively. A stroke sensor 4 that can be pushed and pulled together with the expansion and contraction of the 3L and 3R pistons is provided. Further, as shown in FIG. 2, a lock hole 32 penetrating the rear axle case 14 and the wheel support case 37 is opened in the upper part of the left and right rear axle cases 14, and a pin 31 is inserted into this to manually It is configured to fix the tread.
[0011]
In addition, an infrared proximity sensor 30 is provided inside the left and right fenders 29 of the tractor 10, and when changing the tread, the alarm buzzer 5a is sounded when the tire and the fender 29 approach a predetermined value or more, The liquid crystal monitor 5b is configured to display “warning”.
Thereby, the switching control valves 44, 44 in the hydraulic circuit are switched by the energization command of the controller 23, the pressure oil of the pump P is communicated to the hydraulic cylinder 3 for changing the tread, and the piston is expanded and contracted, The tread of the rear wheel 2 is changed. Further, the proximity sensor 30 can prevent accidental contact between the tire and the fender 29 when tires having different widths are mounted in correspondence with various operations and damage both.
[0012]
In the figure, reference numeral 40 denotes a shaft for transmitting power to the rear wheel differential device 36, and 41 denotes a brake disk that can be pressure-bonded independently by the brake hydraulic cylinder. Further, the tread of the front wheel 1 of the tractor 10 is configured to expand and contract in the same manner.
As shown in FIG. 6, the controller 23 of the tractor 10 includes a CPU for processing various signals, an EEPROM for storing various control programs, a RAM for detecting the signals and setting values, a timer, and the like. Yes. The input unit includes a potentiometer 20 for the working machine lifting lever 19, a lift arm angle sensor 28, a tread change on / off switch 21, a tread width setting device 22, and a tread change hydraulic cylinder 3 for the left and right rear wheels 2, 2. , 3 are connected to stroke sensors 4, 4 that detect the amount of piston expansion and contraction, proximity sensors 30, 30, and the like.
[0013]
In addition, the output section is provided with solenoids 42a and 42b of a proportional pressure control valve for raising or lowering a lift arm for supplying pressure oil to the hydraulic cylinder 25 for raising and lowering the work implement, and left and right brakes. Solenoids 43L and 43R of proportional pressure control valves that brake independently, solenoids 44a and 44b of switching control valves 44 and 44 that expand and contract pistons of the left and right tread changing hydraulic cylinders 3 and 3, and an alarm buzzer 5a and a liquid crystal monitor 5b are connected to each other .
[0014]
Or tread changing device configuration the tractor 10 as operates as the control flowchart of FIG.
First, when the engine key switch of the tractor 10 is turned on to turn on the power, the tread on / off switch 21, various sensors such as the tread width setting device 22, stroke sensors 4 and 4, and the connection state of the setting device are connected. And the setting state is read (STEP 1 and 2).
[0015]
Then, in STEP 3, it is determined whether or not the values of the stroke sensors 4 and 4 are different from the standard state (the cylinder piston is in the shortest state), that is, whether the tread is in the changed state. While the alarm buzzer 5a is sounded, the display “in tread change” is displayed on the liquid crystal monitor 5b as shown in FIG. 5 (STEPs 4 and 5). At the same time, the solenoids 43L and 43R of the proportional pressure control valve are energized to operate the brake hydraulic cylinders of the left and right rear wheels 2 and 2 to prevent the vehicle from starting (STEP 6). Then, the operation set in the EEPROM in advance to release the brake state of the left and right rear wheels 2 and 2, here, the tread change on / off switch 21 is changed from “ON” to “OFF” or from “OFF” to “ON”. When operated, the alarm buzzer 3a is stopped, the display of the liquid crystal monitor 3b is turned off (STEP 8), and the energization of the solenoids 43L and 43R of the proportional pressure control valve is stopped (STEP 9). A tread changing process or the like that becomes a tread in accordance with is performed.
[0016]
As for the tread changing process, as shown in FIG. 9, the solenoids 44a and 44b of the switching control valves 44 and 44 are set so that the set value of the tread width setting device 22 and the target angle of the stroke sensors 4 and 4 coincide. To energize. Here, if the detected value of the stroke sensor does not reach the target value even after elapse of the predetermined time T1 after energization in STEP 5, it is determined that there is some failure, the alarm buzzer 5a is activated, and “tread manual lock” In addition, when the predetermined time T2 (T1 <T2) elapses in STEP 9, the left and right brakes are actuated to temporarily check the traveling of the tractor 10 as described above. .
[0017]
The tread changing device for the tractor 10 configured as described above is configured to notify the alarm buzzer 5a or the liquid crystal display when the treads of the rear wheels 2 and 2 are changed when the engine is started. In this way, it is possible to prevent such a problem that the vehicle travels as it is and touches an obstacle on the side of the vehicle or interferes with the steering operation.
[0018]
In addition to the operation of the alarm buzzer 5a and the warning display on the liquid crystal monitor 5b, the structure is such that only the warning to the operator by the notification is made because the start is temporarily stopped by operating the rear wheel brake of the tractor 10. On the other hand, the said subject can be prevented reliably.
Next, another embodiment of the invention will be described.
[0019]
The control flowchart shown in FIG. 8 shows that when the left and right rear wheels 2 and 2 of the tractor 10 are separately expanded and contracted, when the piston expansion amounts of the left and right hydraulic cylinders 3 and 3 are different, that is, the tread is changed. In this case, the alarm buzzer 5a or a liquid crystal display is used for notification as in the case described above, and the start is temporarily checked by operating the rear wheel brake.
[0020]
Further, as the “control means for temporarily checking the tread”, the brake of the tractor 10 is operated, but instead, for example, the power transmission of the clutch or the transmission is kept in the “off” state by the actuator, As a configuration for checking the start of the engine 12, a configuration for releasing it by a preset operation as described above may be used.
[Brief description of the drawings]
FIG. 1 is a horizontal sectional view of a front axle case showing a tread changing device.
FIG. 2 is a view showing a manual lock on an upper part of a rear axle case.
FIG. 3 is an overall side view of the tractor.
FIG. 4 is an overall rear view of the tractor.
FIG. 5 is a front view of a meter panel.
FIG. 6 is a block diagram showing a connection state of a controller.
FIG. 7 is a flowchart showing an outline of control.
FIG. 8 is a flowchart showing an outline of another form of control.
FIG. 9 is a flowchart showing tread change processing.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Front wheel 2 Rear wheel 3 Tread change hydraulic cylinder 4 Stroke sensor 5a Alarm buzzer 5b LCD monitor 6 Controller

Claims (2)

An actuator ( 3 ) for changing the tread of the front wheel ( 1 ) or the rear wheel ( 2 ) of the vehicle and a sensor ( 4 ) for detecting the tread, and the front wheel ( 1 ) or rear of the vehicle when the engine is started A tread change device for a work vehicle, comprising means ( 5a, 5b ) for notifying by sound or display when it is detected that the tread of the wheel ( 2 ) is in a changed state. An actuator ( 3 ) for changing the tread of the front wheel ( 1 ) or the rear wheel ( 2 ) of the vehicle and a sensor ( 4 ) for detecting the tread, and the front wheel ( 1 ) or rear of the vehicle when the engine is started A tread change device for a work vehicle, comprising: control means ( 6 ) for temporarily stopping the start of the vehicle when it is detected that the tread of the wheel ( 2 ) is in a changed state.

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