JP2000309499A - Control device for booming working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for a booming working vehicle, offering improved workability and enhanced safety without the need for changing the operation amount of a lever corresponding to the weight of mounting matters on a working table at operating a boom. SOLUTION: A boom is provided on a body in a derricking, expandable and turnable manner and a working table is secured to the tip of the boom to form a high lift working vehicle. A controller 43 controls the operation of actuators 16-18 to operate the boom at almost the same speed independently of the size of a load W of the working table, in accordance with the derricking angle θ, length L and turning angle ϕ of the boom 14 detected by detectors 29-31 and the load W of the working table detected by a load detector 3, when the operation amount of an operating lever 25 is the same.

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 a boom-type work vehicle which is constructed by attaching a work device to a tip end of a boom capable of freely moving up and down provided on a vehicle body.

[0002]

2. Description of the Related Art As such a boom type working vehicle, for example, a boom type aerial working vehicle in which a boom is provided so as to be able to move up, down, extend, and turn, and a work table is attached to a tip end of the boom. It has been known. In such a boom-type aerial work vehicle, hydraulic pressure control is performed via a controller by operating an operation lever provided on a work table or a lower part of a vehicle body, thereby operating an actuator to operate the boom, thereby performing work. The table can be moved to a desired position.

[0003] The controller always keeps track of the boom posture based on information on the boom angle, length and turning angle detected by the detector, and when the operating lever is operated, the boom posture at that time is displayed. Actuation control of the actuator (control of hydraulic oil supplied to the actuator) is performed according to the operation amount of the operation lever. Here, if the boom posture is the same, the controller increases the flow rate of hydraulic oil supplied to the actuator as the operation amount of the operation lever increases, causing the work table to move at high speed. The smaller the is, the smaller the supply flow rate is, so that the worktable moves at a low speed.

[0004]

However, in such control, the controller controls the operation of the actuator based only on the boom posture and the operation amount of the operation lever. Therefore, when the lever is operated with the same operation amount, Even when the load on the workbench was large, the operating speed of the boom was changed depending on the magnitude of the load. For this reason, conventionally, in order to smoothly operate the boom, it is necessary to estimate the weight of the load on the work table, that is, the number of workers on the work table and the weight of the mounted tools, and to operate the lever with an operation amount commensurate with such weight. Operation had to be performed and workability was poor. Further, when the lever is operated by mistake in estimating the weight, the boom may be operated at an unnecessarily high speed.

The present invention has been made in view of such a problem, and there is no need to change the lever operation amount according to the weight of the work table mounted when operating the boom, thereby improving workability. It is another object of the present invention to provide a control device for a boom-type work vehicle capable of improving safety.

[0006]

In order to achieve the above object, a control device according to the present invention is provided on a vehicle body and on the vehicle body, and includes an actuator (for example, the turning motor 16, the telescopic cylinder 17, Undulating cylinder 18)
, A working device attached to the tip of the boom (for example, the workbench 21 in the embodiment), and command means for issuing an operation command for the boom by an external operation (for example, the embodiment) Operating lever 2 in
5) and a controller that controls the actuator to operate the boom at a speed corresponding to the operation amount of the commanding means (for example, a high work vehicle in the embodiment). 10), a load detecting unit (for example, the load detector 32 in the embodiment) for detecting a load applied to the working device is provided, and the controller determines the magnitude of the load applied to the working device when the operation amount of the command unit is the same. Regardless of the above, the actuator is operated based on the detection information from the load detecting means so that the boom operates at substantially the same speed.
Here, the operation amount of the command means is an operation amount from the neutral position.

Here, when the actuator is operated by receiving the hydraulic oil (that is, when the actuator is a hydraulic actuator), the controller increases the number of actuations as the load detected by the load detector increases. Control to supply oil to the actuator. By doing so, the operating speed of the boom can be kept constant even when the applied load is large.

According to such a control device, when the operation amount of the command means is the same, the boom is controlled to always operate at substantially the same speed regardless of the magnitude of the load applied to the working device. Since the operator can always operate the command means with the same feeling without considering the magnitude of the load acting on the work device, the workability is improved. Also, for this reason, there is no possibility of operating the boom at an unnecessarily high speed by erroneous operation feeling, so that safety is enhanced.

Further, in the above control device, in response to a change in the amount of operation of the command means, the controller sets the actuator so that the rate of change in the operating speed of the boom becomes smaller as the load detected by the load detector increases. It is preferable to perform the operation control. In this way, when the operation speed of the boom is changed by changing the operation amount of the command means in addition to when the operation of the boom is started or stopped, when the load applied to the working device is large, the boom tip is actuated. The load (inertia force acting on the entire working device) to be applied becomes excessive and the boom can be prevented from becoming insufficient in strength.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. FIG. 2 is an aerial work vehicle 1 which is a boom type work vehicle equipped with the control device according to the present invention.
0 is shown. The vehicle body 11 of the aerial work vehicle 10 is configured based on a truck, and has a driver's seat 11 a and a plurality of traveling wheels 12. A turning table 13 is provided on the vehicle body 11, and a boom 14 in which a plurality of columnar members are nested is attached to the turning table 13 by foot pins 15.

The swivel table 13 is driven by a swivel motor 16 (not shown in FIG. 2) incorporated in the swivel table 13 and is capable of turning in a horizontal plane. Boom 1
The extension cylinder 4 can be extended and contracted in the longitudinal direction by the operation of an extension cylinder 17 (not shown in FIG. 2) built in the boom 14 itself, and an up / down cylinder 18 provided between the boom 14 and the swivel table 13. It is possible to raise and lower by operation. Outrigger jacks 19 are provided at the front, rear, left and right of the vehicle body 11 to extend laterally and downwardly of the vehicle body 11 and support the vehicle body 11 by a plurality of built-in hydraulic cylinders (not shown).

A vertical post 20 is attached to the tip of the boom 14 so as to be able to swing back and forth.
At the upper end of the reference numeral 0, a worktable 21 for boarding the worker is provided so as to freely swing horizontally. A leveling cylinder 22 is provided in the vicinity of the vertical post 20 so that the worktable 21 is always kept horizontal regardless of whether the boom 14 is up or down.

An upper operating device 23 is provided on the work table 21 and a lower operating device 24 is provided on the rear side of the vehicle body. And a turn command of the turntable can be issued. Operation lever 25
Is capable of tilting to the front and back, right and left, and twisting around the axis from the neutral position extending vertically, and the up and down command of the boom 14 is issued by the forward and backward tilting operation, and the expansion and contraction command of the boom 14 is issued by the right and left tilting operation. In addition, a turning command of the turntable 13 (that is, a turning command of the boom 14) can be performed by the twisting operation. The operation amount σ1, the operation amount σ2, and the twist operation amount σ3 of the forward / backward tilting of the operating lever 25 are respectively the potentiometers 26,
27 and 28 (not shown in FIG. 2).

At the base end of the boom 14, an undulation angle detector 2 is provided.
9, a length detector 30 is provided at the tip of the boom 14 so that the undulation angle θ and the length L of the boom 14 can be detected. A swivel angle detector 31 is provided below the swivel base 13 so that the swivel angle of the swivel base 13 (that is, the swivel angle of the boom 14) φ is detected. Work table 2
A load detector 32 (not shown in FIG. 2) is provided at a lower portion of 1, so that a load W of the work table 21 can be detected.

FIG. 1 shows a configuration of a control device of the aerial work vehicle 10. As shown in this figure, the swing motor 16, the telescopic cylinder 17, and the up-and-down cylinder 18 (hereinafter, all or one of them is referred to as an actuator)
It operates by receiving hydraulic oil supplied from a hydraulic pump 42 driven by an engine 41 provided therein. The supply of the operating oil to the actuator is controlled by an operation signal output by operating an operation lever 25 provided on the upper operation device 23 or the lower operation device 24 (information on the operation amounts σ1, σ2, σ3 of the operation lever 25). The control is performed by the controller 43 electromagnetically driving the control valve 44 based on the above.

The controller 43 is constantly input with information on the up-and-down angle θ, length L and turning angle φ of the boom 14 detected by the detectors 29 to 31.
2 or when the operation lever 25 of the lower operation device 23 is operated, control is performed to operate the actuator so that the boom 14 operates at a speed corresponding to the operation amounts σ1, σ2, σ3 (supplied to the actuator). Control the hydraulic oil).

Here, the controller 43 includes the detectors 29 to
Detection information (θ, L, φ) and load detector 32
When the operation amount of the operation lever 25 is the same on the basis of the detection information (W) from the controller, the actuator is operated so that the boom 14 operates at substantially the same speed regardless of the magnitude of the load W of the work table 21. Control for operating 16 to 18 is performed. Specifically, as the moment acting around the foot pin 15 of the boom 14 is larger, that is, as the undulation angle of the boom 14 is smaller, as the length of the boom 14 is larger, and the load W of the worktable 21 is smaller. The larger the oil, the more hydraulic oil
8 (the control valve 44 is driven to the open side). As described above, the controller 43 controls the supply of more hydraulic oil to the actuator as the load W of the workbench 21 increases, so that the operating speed of the boom 14 is kept constant even when the load is large. can do.

As described above, in the above control device, when the operation amount of the operation lever 25 is the same, the boom 14
Is controlled so as to always operate at substantially the same speed regardless of the magnitude of the load applied to the workbench 21, and the operator can reduce the load (the number of work vehicles, the weight of the load, etc.) acting on the workbench 21. Since the operation lever 25 can always be operated with the same feeling without consideration, the workability is improved. Also, for this reason, there is no possibility of operating the boom 14 at an unnecessarily high speed by erroneous operation feeling, so that safety is enhanced.

When the operation amount of the operation lever 25 changes, such as when the operation amount of the operation lever 25 is changed while the boom 14 is operating, in addition to when the operation of the boom 14 is started or stopped, the controller 43 changes the drive amount of the control valve 44 to change the flow rate of the working oil supplied to the actuator, so that the operation speed of the boom 14 becomes a speed corresponding to the changed operation amount. Specifically, when the operation amount of the operation lever 25 is increased, the operation speed of the boom 14 is increased by increasing the amount of hydraulic oil supplied to the actuator, and when the operation amount of the operation lever 25 is reduced. The operation speed of the boom 14 is reduced by reducing the amount of hydraulic oil supplied to the actuator.

Here, the controller 43 operates the operation lever 2
5 is operated suddenly, the boom 1
Instead of suddenly operating the actuator 4, the actuator is controlled so that the operating speed of the boom 14 changes slowly so that the inertial force acting on the boom 14 from the work table 21 does not become excessive. Function is called shockless). For example, as shown in FIG. 3A, the operation amount σ of the left and right tilting of the operation lever 25 (extension and contraction of the boom 14).
2 is increased from σ21 to σ22 in a substantially step-like manner, the controller 43 changes the operation speed V of the boom 14 from the operation speed V1 corresponding to the operation amount σ21 to the operation amount as shown in FIGS. 3B and 3C. Operating speed V2 corresponding to σ22
Steps in multiple steps until the time Δ
The operation of the actuator (the telescopic cylinder 17 in this case) is controlled so as to change over t (the drive control of the control valve 44 is performed).

Here, the time Δt is set so as to be larger as the load W of the work table 21 detected by the load detector 32 is larger.
The change rate (ΔV / Δt) of the operating speed of the work table 4 becomes smaller as the load W of the workbench 21 increases. FIG. 3B shows a case where the load W is small.
Indicates a case where the applied load W is large.

As shown in FIGS. 3B and 3C, when Δt is set large, the number of steps from V1 to V2 is set to be large. The width can also be set arbitrarily, and by optimizing the number of steps and the width of each step, an actuator (here, a telescopic cylinder is used) such that the operating speed of the boom 14 smoothly changes from V1 to V2 at the set time Δt. The operation control of 17) is performed. The step width corresponds to the output continuation time of the same drive signal (drive signal for driving the control valve 44 with the same drive amount) output from the controller 43 (the controller 43 corresponds to the clock frequency of the processor). The drive signal is output continuously in each cycle.) Further, as can be understood from FIGS. (B) and (C), even when the time Δt is the same, the operating speed of the boom 14 changes more smoothly as the number of steps increases.

Such control is performed not only when the operating speed of the boom 14 is increased as in the above example, but also when the boom 14 is operated.
The same applies to the case where the operating speed decreases.
However, the set time Δt is set to be smaller than when the operation speed of the boom 14 increases. This is because, when stopping or decelerating the operation of the boom 14, it is preferable that the response of the operation of the boom 14 be fast in terms of safety. Also, the control shown in the above example is based on the boom 14
The same applies to the case of undulation and turning.

As described above, in the above control device, when the operation amount of the operation lever 25 changes, the change in the operating speed of the boom 14 increases as the load applied to the work table 21 detected by the load detector 32 increases. When the operation speed of the boom 14 is changed by changing the operation amount of the operation lever 25 in addition to when the operation of the boom 14 is started or stopped, or when the operation speed of the boom 14 is changed, Boom 1 when the load of 21 is large
4 It is possible to prevent a situation in which the load (inertial force acting on the entire working device) acting on the distal end portion becomes excessive and the boom 14 becomes insufficient in strength.

Although the embodiment of the control device according to the present invention has been described above, the present invention is not limited to the above embodiment. For example, the target to which this control device is applied is not limited to the aerial work vehicle 10 of the above-described form, and may be another form of the aerial work vehicle. Further, the working device is provided at the tip of the boom. Other working vehicle, for example, a crane truck or the like. Also, the actuator for operating the boom need not be hydraulic, but may be an electric drive.

[0026]

As described above, according to the control device for a boom type working vehicle according to the present invention, when the operation amount of the command means is the same, the boom is not affected by the magnitude of the load applied to the working device. Regardless, the operation is controlled so as to always operate at substantially the same speed, and the operator can always operate the command means with the same feeling without considering the magnitude of the load applied to the working device, thereby improving workability. . Also, for this reason, there is no possibility of operating the boom at an unnecessarily high speed by erroneous operation feeling, so that safety is enhanced.

Further, in the above control device, in response to a change in the operation amount of the command means, the controller sets the actuator so that the rate of change in the operating speed of the boom becomes smaller as the load detected by the load detector increases. It is preferable to perform the operation control. In this way, when the operation speed of the boom is changed by changing the operation amount of the command means in addition to when the operation of the boom is started or stopped, when the load applied to the working device is large, the boom tip is actuated. The load (inertia force acting on the entire working device) to be applied becomes excessive and the boom can be prevented from becoming insufficient in strength.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a control device according to the present invention.

FIG. 2 is a side view of an aerial work vehicle equipped with the control device.

3A and 3B are diagrams illustrating an example of a change in the operating speed of the boom when the operation amount of the operation lever is changed, wherein FIG. 3A is a diagram illustrating a time change of the operation amount of the operation lever, and FIG. (A)
(C) is a change in the operating speed of the boom corresponding to (A) and a change in the operating speed of the boom corresponding to (A), and the load applied to the work table is large. FIG.

[Explanation of symbols]

 Reference Signs List 10 Work platform aerial vehicle (boom type work vehicle) 11 Body 14 Boom 16 Swivel motor (actuator) 17 Telescopic cylinder (actuator) 18 Undulating cylinder (actuator) 21 Work table (working device) 25 Operation lever (command device) 32 Load detection (Load detecting means) 43 Controller

Claims (3)

[Claims] 1. A vehicle body, a boom provided on the vehicle body and capable of raising and lowering by actuation of an actuator, a working device attached to a tip end of the boom, and an operation command of the boom by an external operation. A control device for a boom-type work vehicle, comprising: a commanding means for performing the operation; and a controller for performing control for operating the actuator so that the boom operates at a speed corresponding to an operation amount of the commanding means. A load detecting means for detecting a load applied to the working device, wherein the controller is configured such that when the operation amount of the command means is the same, the boom is substantially the same regardless of the magnitude of the load applied to the working device. Controlling the actuator based on detection information from the load detection means so that the actuator operates at a speed. Control device. 2. The method according to claim 1, wherein the actuator is actuated by receiving hydraulic oil, and the controller performs control to supply more hydraulic oil to the actuator as the load detected by the load detector increases. A control device for a boom type work vehicle. 3. In response to a change in the operation amount of the command means,
3. The controller according to claim 1, wherein the controller controls the operation of the actuator such that the rate of change in the operation speed of the boom decreases as the load detected by the load detector increases. 3. Boom type work vehicle control device.