JPH05207803A - Apparatus for controlling height of working machine of power vehicle - Google Patents

Abstract

PURPOSE:To easily and quickly perform delicate control of tilling depth by placing a specific lifting operation means and a controlling means near a steering wheel. CONSTITUTION:Switches S1, S2, S3, etc., operated by a mode-changing switch 69 and a lifting lever 74 are placed near a steering wheel 61. The switch S1 lifts a working machine to a preset level and the switches S2 and S3 delicately control the height of the working machine within a prescribed range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a working machine lifting control device for lifting a working machine connected to a tractor or a small riding management machine.

[0002]

2. Description of the Related Art Conventionally, as a device of this type, a position lever is provided beside a seat, and the position lever is operated back and forth to elevate and lower a working machine connected to the rear part of the machine body. In addition, in order to quickly raise and lower the working machine when turning at the ridge, a push button switch type operation means is provided separately from the position lever. There is one that controls to lower to the original position set by the position lever when pressed.

[0003]

The above-mentioned conventional device is
Since the work lever was also configured to be able to move up and down from the lowered position to the maximum raised position by the position lever, the amount of movement of the lifting link by the position lever is large, and therefore the work device is moved slightly up and down during work. Was extremely difficult.

A position lever is used for fine adjustment.
However, if the range of rotation is expanded, the panel of the operation part and the guide part must be expanded, and the amount of movement of the operator's arm also becomes large, which causes fatigue. was there.

[0005]

In order to solve the above problems, the present invention takes the following technical means.
That is, it is provided with a position lever 66 for adjusting and changing the elevation height of the ground work machine and a connection link 18 connecting the work machines, and the connection link 18 is positioned at the height set by the position lever 66. In a power vehicle with a position control for controlling so that the working machine is lifted up and down near the steering wheel 61 to a preset height, and an adjustment for slightly lifting the working machine with a predetermined width is provided. It is characterized in that the working machine lifting control device in a power vehicle is provided with means S2 and S3.

[0006]

Embodiments of the present invention will now be described based on the embodiments shown in the drawings. First, the structure will be explained as follows.
Is a tractor for passenger management, which is provided with front wheels 2, 2 and rear wheels 3, 3 at the front and rear portions of the body, and these front and rear wheels 2, 3 can be steered individually or in conjunction with each other. Has been done.

A vertical axis type engine 5 is provided in the hood 4 of the tractor 1, and the rotational power of the engine 5 is transmitted via a power transmission means 6 including pulleys 6a, 6b and a belt 6c. This is transmitted to the transmission in case 7. Two power take-off shafts 9 and 10 are mounted on the rear part of the mission case 7, and the upper take-out shaft 9 is a universal shaft.
It is transmitted from the transmission case 11 via the monkey joint 12 to the PTO input shaft 14 which is provided so as to project forward.

In the rear part of the transmission case 11, the rearward P
The TO shaft 15 is mounted on a protruding shaft, and the PTO shaft 15 is used as a power take-off shaft for driving a working machine such as a rotary connected to the rear part of the machine body. Reference numeral 18 denotes a connecting link for raising and lowering the working machine, which is vertically rotated by two lift cylinders 21 and 21 provided at the rear ends of the left and right frames 20.

The rotational power decelerated by the transmission in the transmission case 7 is transmitted to the front axle housing 25.
And via a differential device (not shown) in the rear axle housing 28 to the front wheels 2, 2 and the rear wheels 3, 3, respectively. 29 is a change lever. Next, the front wheel steering system F and the rear wheel steering system R will be described based on the hydraulic circuit diagram shown in FIG. Reference numerals 30 and 30 denote knuckle arms for the front wheels 2 and 2, and both knuckle arms 30 and 30 are connected by a tie rod 31.

33, 33 are knuckle lures of the rear wheels 3, 3.
Reference numerals 35 and 35 are tie rods for connecting the knuckle arms 33, 33. The arm 37 provided above the knuckle arm 30 of the right front wheel 2 and the center of the lower part of the machine are connected by a single rod hydraulic cylinder 40, and the front part of the knuckle arm 33 of the right rear wheel 3 and the machine body. A hydraulic cylinder-44 is interposed between and.

Reference numerals 45 and 46 are steering angle sensors for detecting the steering angles of the right front wheel 2 and the rear wheel 3. 50 is a front wheel steering system F
It is an electromagnetic valve that controls the two-position, four-port type valve, and normally includes the hydraulic pump 52 side and the hydraulic cylinder-4.
When the solenoid 53 of the solenoid valve 50 is energized and the solenoid valve 53 is in communication with the 0 side, the chamber is switched to the right side and the oil passage between the hydraulic pump 52 side and the hydraulic cylinder 40 side is cut off.

Reference numeral 55 is an electromagnetic valve for controlling the rear wheel steering system R, which is composed of a two-position four-port type valve, and normally disconnects the hydraulic pump 52 side and the hydraulic cylinder-44 side from each other. When the solenoid 58 is energized, the chamber is switched to the right chamber, and the hydraulic pump 52 side and the hydraulic cylinder-4 are connected.
The oil passages on the 4th side are in communication. Reference numeral 60 denotes an all-hydraulic steering mechanism. When the steering handle 61 is turned, the oil passage and the oil amount are controlled.

For example, in the figure, when the steering handle 61 is turned to the right, the operating pressure oil sent from the hydraulic pump 52 passes through the oil passage (a) into the chamber on the left side of the electromagnetic valve 50, and the hydraulic cylinder-- The piston rod of 40 is pushed out to cut the front wheels 2 and 2 to the right, and the returned working pressure oil returns to the tank 63 through the chamber on the left side of the electromagnetic valve 55. On the contrary, when the steering handle 61 is turned to the left, the operating pressure oil sent from the hydraulic pump 52 passes through the oil passage (b) into the left chamber of the electromagnetic valve 55 and retracts the piston rod of the hydraulic cylinder-40. Then, the front wheels 2 and 2 are turned to the left, and the returning pressure oil is collected in the tank 63.

Reference numeral 65 denotes a proportional electromagnetic main control valve for controlling the lifting and lowering of a working machine connected to the rear part of the tractor 1. The operator grips the position lever 66 and rotates it in the front-back direction. Lift cylinder-21,2
The working pressure oil flows in or is discharged into the inside of the pipe 1 to raise or lower the connecting link 18. Position lever-6
A ground height setting device 68 for setting the ascending / descending height of the working machine is attached to the rotation base of 6, and a rotation height support device 70 for detecting the ascending / descending height is provided at the rotation pivot support part of the connecting link 18. Is attached. Therefore, position lever 6
When 6 is rotated back and forth, the ascending side proportional solenoid 65a or the descending side proportional solenoid 65b of the main control valve 65 is excited according to the deviation between the set value and the detected value, and the flow rate is controlled.

FIG. 3 is a perspective view of the support portion of the steering handle 61. On the lateral side of the handle post 71, an elevation lever 74 for raising and lowering the working machine is provided separately from the position lever 66. ing. Lifting lever 74
Can be moved in the up-down direction and the front-rear direction in a cross shape, and as will be described later, once the up-and-down lever 74 is turned up and down and the switch S1 is turned on, the working machine is raised to the maximum raised position. When the elevating lever 74 is moved up and down again to turn off the switch S1, the working machine descends to the original height set by the position lever 66.

When the elevating lever 74 is rotated backward to turn on the switch S2, the working machine can be raised slightly. In this embodiment, the connecting link 18 is rotated upward by a minute angle Δh which is set so that the switch S2 is turned on once. On the contrary, when the elevating lever 74 is rotated forward to turn on the switch S3, the connecting link 18 descends by a minute angle Δh.

The passenger management tractor-1 described in this embodiment has three solenoid valves 53 and 58 controlled by combining the solenoids 53 and 58 of the electromagnetic valves 50 and 55 as follows. The steering mode can be selected. That is, in the OFF state where neither solenoid 53, 58 is energized, the front wheel steering mode is set, and when both solenoids 53, 58 are turned ON, the rear wheel steering mode is set. 58
When the switch is turned on, the front and rear wheels 2 and 3 are switched to the front and rear wheel antiphase steering mode in which the front and rear wheels 2 and 3 face in opposite directions.

These modes are switched by a mode selector switch 69 provided in the vicinity of the cockpit, and the front wheels 2, 2 and the rear wheels 3, 3 are switched in a straight direction in order to switch between the modes. It is configured to be possible when facing. This steering system has a manual steering mode and an automatic steering mode.
In the mode, the steering mode set by the operator is prioritized. In the automatic steering mode, when the working machine is raised, the steering mode changes to the front-rear wheel antiphase steering mode, and when the machine body is moved backward, the steering mode shifts to the rear wheel steering mode.

Next, the block diagram shown in FIG. 4 will be described. Steering angle sensors 45 and 46 for detecting the steering angles of the front wheels 2 and 2 and the rear wheels 3 and 3 are connected to a control unit 76 including a microcomputer via an A / D converter 75. Furthermore, this A /
The D converter 75 includes a position ground height setting device 68,
The ground height detector 70 is connected, and the control unit 76 has
The mode changeover switch 69 and the switches S1, S2, S3, etc. operated by the elevating lever 74 are respectively connected. Reference numeral 78 is an automatic / manual switch, and 80 is a reverse detection switch.

On the other hand, on the output side of the controller 76, the proportional control valves 65a and 65b, the front wheel steering mode display lamp L1, the rear wheel steering mode display lamp L2, and the front and rear wheel antiphase steering mode display lamps. L3, an automatic status display lamp L4, and solenoids 53 and 58 of electromagnetic valves 50 and 55 are connected. The programs of FIGS. 5 to 8 are stored in the memory of the control unit 76, and the contents will be described below.

FIG. 5 shows a main flow chart for controlling the lifting and lowering of the working machine. At a stage before the control is started while the engine is stopped, the position lever is unexpectedly measured by a third party. When it is moved, the safety mode is designed to work first so that the hydraulic equipment does not suddenly start when the engine is started. In order to release this safety mode, it is necessary to operate the position lever 66 appropriately so that the position set value θp and the detected value θe substantially coincide with each other.

When the two values θp and θe coincide with each other or the absolute value of the difference between them is smaller than the set value α, the safety mode is released and the working machine is set to the height set by the position lever 66. Move up and down. Now, lift lever 7
When the switch S1 is turned on and off by operating the switch 4 in the vertical direction, the work implement rises to the maximum raised position according to the flow chart shown in FIG.
It descends to the position set in 66.

When the working depth is finely adjusted during the work, or when the position of the connecting link 18 is finely adjusted up and down when the working machine is detached, as shown in FIG. 7 and FIG. By rotating -74 forward or backward, switches S2 and S3 are appropriately turned on and off to slightly rotate the connecting link 18 up and down to a desired position. As is clear from the main flow chart, in this embodiment, when the working machine is finely adjusted up and down by using the lifting lever 74, the setting of the position lever 66 and the connection link 18 are performed. Since the heights do not match, I try to return to safety mode once. Therefore, in order to get out of this safety mode, the position lever 66
Must be moved back and forth again to match the position setting value with the detected value.

As described above, the position lever 66 is used to greatly raise or lower the working machine, and the lifting lever 7 is used to vertically adjust the working machine within a minute range.
Since it is sufficient to operate 4 in the front-back direction, the operability is significantly improved. Moreover, in this embodiment, one lifting lever 74
Since the work machine can be rotated to the maximum raised position, returned to the original position and returned to the original position, and finely adjusted up and down from the set position of the position lever 66, the structure is simple and simple. The feature is that it can quickly respond to the adjustment of the working depth on the ridge.

Next, a partial improvement device for the riding management tractor-1 used in this embodiment will be briefly described with reference to FIGS. 9 to 13. FIG. 9 shows an ultrasonic Doppler sensor attached to the lower part of the abdomen of the tractor 1 so that the vehicle speed can be detected. The characteristic is that this ultrasonic Doppler sensor detects the actual vehicle speed in the low speed range. To display this,
The high-speed range is the point where the theoretical vehicle speed calculated from the rotation of the wheels is displayed regardless of the ultrasonic Doppler sensor.

In the figure, reference numeral 85 is an ultrasonic Doppler sensor, 86 is a pickup device for detecting the number of revolutions, which is arranged near the final reduction gears (not shown) of the rear wheels 3 and 3, and 87.
Is an input interface, 88 is a CPU, 89 is an output interface, and 90 is a display panel. In the case of the ultrasonic Doppler sensor-85, the Doppler shift frequency is larger than that of the Doppler sensor using microwaves,
It is difficult to detect the vehicle speed in the high speed range by the sensitivity characteristic of the ultrasonic microphone using the ceramic piezoelectric element or the like. If it is attempted to accurately capture not only the low-speed range but also the high-speed range, the sensor will be expensive, but the tractor is originally required to detect the slip ratio during work. In other words, the original purpose can be achieved if the working speed at low speed can be accurately detected, and the theoretical vehicle speed obtained from the final reduction gear in the mission case is sufficient for higher speeds, and it is cost effective. But that would be cheaper.
FIG. 10 shows a display range. Below about 15 km / h, the speed calculated using the ultrasonic Doppler sensor-85 is displayed on the display panel 90 below that, and the theoretical vehicle speed is displayed above 15 km / h. I am trying.

In FIGS. 11 and 12, one display device is used to display the vehicle speed and the slip ratio, and the connecting link 18 is rotated upward to lift a predetermined amount. The vehicle speed is displayed when the height is reached, and the slip ratio is displayed when the connecting link 18 descends to perform work. Next, FIG.
To briefly explain the electric circuit shown in FIG. 3, this circuit is designed so that the transistor in the controller is not destroyed when the polarity of the battery 92 is incorrectly connected.

In the figure, reference numerals F1, F2, F3, F4, and F5 are fuses, 93 is a starter motor, 94 is a starter relay, 95 is an alternator, 96 is a regulator, and 97 is illumination. ,, horn, winker load, 98 control
La, 99 is a key switch, 100 is a relay, 101 is the relay switch, and 102 is a diode directly connected to the relay 100.

When the key switch 99 is turned off, the terminal B'and the terminal E are connected. When the key switch 99 is turned to the on state, the terminal BAT and the terminal IG are connected, and the key is further turned on. When the switch 99 is turned to start the engine 5, the terminal BAT, the terminal IG, and the terminal ST are connected. Connect the Battery-92 in the proper condition and press the key.
When the switch 99 is turned, the relay 100 is actuated, the relay switch 101 is closed, and the electric current flows into the controller 98.

On the contrary, when the polarity of the battery 92 is incorrectly connected, the relay 100 does not operate, and therefore the power is not supplied to the controller 98, so that the output transistor of the controller 98 is destroyed. Can be prevented.
Conventionally, when power is supplied to various solenoids connected to the input side of the controller 98, the solenoid is turned on.
A surge voltage is generated when the N and OFF operations are performed, and diodes must be connected to both ends of all solenoids in order to prevent the surge voltage. However, according to this improved device, the number of diodes themselves is also increased. Since the number is small, the controller breakage prevention device can be constructed inexpensively.

[0031]

As described above, the present invention is provided with the position lever 66 for adjusting and changing the elevation height of the ground working machine and the connecting link 18 connecting the working machines, and is set by the position lever 66. In a power vehicle with position control for controlling the connection link 18 to be positioned at a predetermined height, a raising / lowering operation means S1 for raising and lowering the working machine up to a preset height in the vicinity of the steering wheel 61.
And an adjusting means S2 for slightly moving the working machine up and down with a predetermined width,
Since S3 and S3 are provided, it becomes possible to easily and quickly perform fine adjustment of the working depth during turning and during work.

[Brief description of drawings]

FIG. 1 is an overall side view of a riding management tractor.

FIG. 2 is a hydraulic circuit diagram for explaining the operating principle.

FIG. 3 is a perspective view of a steering handle portion.

FIG. 4 is a block diagram showing a control system.

FIG. 5 is a flowchart showing control contents.

FIG. 6 is a flowchart showing control contents.

FIG. 7 is a flowchart showing control contents.

FIG. 8 is a flowchart showing control contents.

FIG. 9 is a block diagram of an improved device.

FIG. 10 is a diagram illustrating a vehicle speed display range.

FIG. 11 is a block diagram of an improved device.

FIG. 12 is for explaining the contents shown on the display device,
B shows the speed and B shows the slip ratio.

FIG. 13 is a protection circuit diagram of the controller.

[Explanation of symbols]

 1 Riding tractor for management-2 Front wheel 3 Rear wheel 4 Bonnet 5 Engine 18 Connecting link 21 Lift cylinder-40 Hydraulic cylinder-44 Hydraulic cylinder-45 Steering angle sensor-46 Steering angle sensor-61 Steering handle 68 Ground level setter 69 Mode changeover switch 70 Ground height detector 71 Handle post 74 Lift lever

Claims (1)

[Claims] 1. A position lever 66 for adjusting and changing the ascending / descending height of a ground work machine, and a connection link 18 for connecting the work machine, wherein the connection link has a height set by the position lever 66. In a power vehicle with position control for controlling 18 to be positioned, a work machine is finely moved in the vicinity of a steering wheel 61 with a lifting operation means S1 for raising and lowering the work machine to a preset height and a predetermined width. A working machine lifting control device for a power vehicle, comprising: adjusting means S2, S3 for lifting and lowering.