JP2556814Y2 - Elevation control device for working unit in work vehicle - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for raising and lowering a working unit in a working vehicle such as a tractor.

[0002]

2. Description of the Related Art Conventionally, in a working vehicle of this type, a working unit which is connected to a traveling machine so as to be able to move up and down is moved up and down based on the operating position of an elevating lever. However, in this method, when trying to raise the working unit, for example, when the aircraft circulates, it is necessary to operate the lifting lever to the maximum position each time, and it is difficult to operate. Work precision has also been a problem because subtle operations such as fine movement have not been practically performed. Therefore, a neutral automatic return type elevating switch is provided separately from the elevating lever. When the operation time of the elevating switch is within a predetermined time, the working unit is finely moved up and down. There is proposed an operation switching means between a fine movement elevating operation and a continuous elevating operation such as continuously elevating and lowering self-holding to upper and lower limit positions. Conventionally, however, the limit position of the working unit elevating and lowering in the continuous elevating operation is set based on the operation position of the elevating lever and the set position of the lifting restriction volume, and the ascent and descent exceeding the set limit position are strictly restricted. For example, if you want to lower the working part on a trial basis during work, you need to operate the operating lever as before, and if operation is troublesome, move the operating lever exactly to the original position. Since it is not easy to return, there is a possibility that the work accuracy may be reduced, which has been a problem.

[0003]

SUMMARY OF THE INVENTION The present invention has been conceived in view of the above-mentioned circumstances, and has as its object to provide an ascent / descent control device for a working unit in a working vehicle that can eliminate these drawbacks. A lifting / lowering control unit that switches a lifting / lowering operation of the working unit to a fine movement lifting / lowering operation for finely moving / lowering the working unit and a continuous lifting / lowering operation for continuously raising / lowering the working unit to a limit position in a self-holding manner; A limit position setting means for setting the limit position;
When, in a work vehicle comprising providing an elevating switch for the lifting operation of the working unit, the elevator controller, Noboru
The operation time of the descending switch exceeds the preset time
The operation time exceeds the set time
Is set by the limit position setting means.
Move the work unit at high speed to the limit position and do not exceed the set time.
If this is not the case, the
Work up to the lifting range exceeding the set limit position
A fine movement priority control means for allowing a fine movement elevating operation at a low speed of the section . According to the present invention, the operability and the work accuracy can be improved in the work traveling vehicle capable of performing the fine movement elevating operation and the continuous elevating operation of the working unit by this configuration.

[0004]

Next, an embodiment of the present invention will be described with reference to the drawings. In the drawings, reference numeral 1 denotes a traveling body of a tractor, and a rotary tilling type working unit 3 is connected to a rear portion of the traveling body 1 via a lifting link mechanism 2 so as to be able to move up and down. Can be raised and lowered by the swing of the lift arm 5 accompanying the expansion and contraction operation of the hydraulic cylinder 4, and these basic configurations are all conventional.

Reference numeral 6 denotes a position lever disposed on the side of the driver's seat 7. The position lever 6 is mounted to be swingable in the front-rear direction. It is detected by a lever angle detection sensor 8 connected to the control unit and is input to a control unit 9 described later.

Further, reference numeral 10 denotes an elevating switch disposed at a position near the rear of the position lever 6, and the elevating switch 10 is an automatic neutral return type toggle switch having three positions of ascending, neutral and descending. It is composed of

On the other hand, the control unit 9 is a control unit constituted by using a micro computer, which comprises the lever angle detection sensor 8 and the up / down switch 1.
In addition to 0, a signal is input from a lifting regulation volume 11 for setting an upper limit of the working unit 3 and an arm angle detection sensor 12 for detecting a swing angle of the lift arm 5,
An operation signal is output to an electromagnetic valve or the like of the hydraulic cylinder 4 based on the determination based on these input signals. That is, the control unit 9 performs position control for raising and lowering the working unit 3 based on the operation position of the position lever 6 and lifting switch control for raising and lowering the working unit 3 based on operation of the lifting switch 10. The control procedure is stored in advance. Note that the control procedure of the position control is the same as the conventional one, and thus the description is omitted.

The control procedure of the elevation switch control will be described in detail with reference to a flow chart shown in FIG. 4. First, it is determined whether or not the elevation switch 10 has been raised, and if this is YES, In addition, the lifting switch 10
It is determined whether or not the operation time T1 is within a preset time T0 (one second in the embodiment). In other words, the control branches based on the operation time of the lifting switch 10,
If the lifting switch 10 is operated for more than the set time T0, the upper limit position of the lift arm 5 is calculated based on the set value of the raising restriction volume 11, and the lift arm 5 is raised at a high speed to the calculated upper limit position. For this purpose, an operation signal is output to the hydraulic cylinder 4 in a self-holding manner. If the operation time T1 of the elevating switch 10 is within the set time T0, an operation signal is output to the hydraulic cylinder 4 to raise the lift arm 5 at low speed.
This low-speed ascending operation is allowed up to the ascending range exceeding the calculated upper limit position, prior to the setting of the raising restriction volume 11.

On the other hand, when the raising / lowering switch 10 is operated to be lowered, the operation time T2 becomes longer than the set time T as in the case of the raising operation.
It is determined whether or not it is within 0. If the up / down switch 10 is operated for more than the set time T0, the lower limit position of the lift arm 5 is calculated based on the lever angle of the position lever 6, and Then, an operation signal is output to the hydraulic cylinder 4 in a self-holding manner so as to lower the lift arm 5 to the calculation lower limit position at a high speed. That is, the working unit 3 temporarily raised to the upper limit position by the above-described lifting operation is self-holdingly lowered at a high speed to the position corresponding to the position lever 6, thereby enabling quick work return. The operation time T2 of the lifting switch 10 is equal to the set time T0.
If it is within the range, an operation signal is output to the hydraulic cylinder 4 to lower the lift arm 5 at a low speed irrespective of the position of the position lever 6, whereby the low-speed lowering operation is performed by the positioning. The lower limit setting based on the position of the lever 6 is prioritized to a lower range exceeding the calculated lower limit position.

In the embodiment of the present invention constructed as described above, when the elevating switch 10 is operated for more than the set time T0, the lift control volume 11 or the limit position calculated based on the position lever 6 is reached. Working part 3
When the lifting switch 10 is operated within a range not exceeding the set time T0 while the lifting unit 10 is raised and lowered in a self-holding manner, the working unit 3 is finely moved at a low speed. The range exceeding the limit position calculated based on the regulation volume 11 and the position lever 6 is allowed. Therefore, when it is desired to slightly raise or lower the working unit 3 beyond the limit position, it is not necessary to operate the positioning lever 6 as in the prior art, and as a result, the operation can be simplified and the operability can be improved. In fact, it is possible to maintain the position lever 6 at a fixed position, thereby improving the working accuracy. And the height to this limit position
Speed up and down and fine movement at low speed that is allowed even if the limit position is exceeded
The use of lifting and lowering is long operation time of the lifting switch 10.
This can be made shorter and the structure can be simplified.

It should be noted that the present invention is not limited to the above-described embodiment. For example, a slight movement of the working unit exceeding the limit position may be permitted on either the ascending side or the descending side. The limit position may be calculated based on operating tools other than the lifting restriction volume and the position lever.

[0012]

[Effects] In summary, since the present invention is constructed as described above, the working unit is moved up and down by the switch.
Fine movement to raise and lower the operation part beyond the limit position
Lifting and lowering the working unit continuously to the set limit position in a self-holding manner
Although it is possible to switch between continuous lifting and lowering,
Switching between continuous lifting to the fixed limit position and fine movement lifting
The operation time of the switch is shortened. As a result,
Selection of lifting and fine movement lifting and lowering
There is no need to provide a switch, and a switch can be used.
As a result, the operability is improved and the structure is simplified.
Can be

[Brief description of the drawings]

FIG. 1 is a side view of a tractor.

FIG. 2 is a plan view of an operation panel.

FIG. 3 is a block diagram schematically showing a control mechanism.

FIG. 4 is a flowchart of a lifting switch control.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Traveling body 3 Working part 6 Position lever 9 Control part 10 Elevating switch

Claims (1)

(57) [Scope of request for utility model registration] A lifting / lowering control unit for switching a lifting / lowering operation of the working unit between a fine lifting / lowering operation for finely lifting / lowering the working unit and a continuous lifting / lowering operation for continuously lifting / lowering the working unit to a limit position in a self-holding manner; The control unit includes a limit position setting unit for setting the limit position, and an operation of lifting and lowering the working unit.
In a working vehicle provided with a lifting switch for performing the operation, the operation of the lifting switch is controlled by the lifting control unit.
Judge whether or not the preset time has been exceeded, and
If the operation time exceeds the set time,
Work section to the limit position set by the
If you move quickly and do not exceed the set time,
Overrides the limit position setting, and sets the set limit position
A lift control device for a working unit in a working vehicle, comprising fine movement priority control means for allowing a fine movement elevating operation at a low speed of the working unit up to a moving range exceeding the moving range .