JP2508376Y2 - Work range display device for boom work vehicle - Google Patents

Description

[Detailed Description of Device] a. The present invention relates to a work vehicle including a boom, such as a crane vehicle and a work platform for aerial work, and a work range display device for a boom work vehicle that displays the work range of the boom. Regarding

(Prior Art) The boom of a boom work vehicle as described above has a boom weight and a tip load of the boom (a hoisting load,
In an aerial work vehicle, the load acts in the direction in which the vehicle body falls due to the weight of the work table and the weight of the work table. If this load exceeds the limit load that can be supported by the outriggers that are projected to the side of the vehicle body or the like, the vehicle body may fall over.

Therefore, when the actual load reaches the limit load, the boom work vehicle is further operated by a boom operation in a direction of increasing the actual load, for example, a direction in which the work radius is expanded such as a hoisting down operation and an extension operation ( An overload prevention device that restricts the movement in the horizontal direction) is installed.

On the other hand, in advance, a device for displaying the ratio of the actual load acting on the boom to the limit load, that is, the load ratio, is often attached in advance so that the operator can grasp the workable range. The load factor is displayed as a percentage with the full load state (the state where the actual load reaches the limit load) as 100%.

(Problems to be solved by the invention) However, the rate of change of the actual load with respect to the increase in the working radius depends on the weight of the boom and the tip load. There is a problem in that it is difficult to determine whether the working radius can be expanded, that is, the distance that the hoisting object or the worktable can move horizontally. Therefore, it is often impossible to determine whether or not the hoisted object or the workbench can be moved to the target position without actually operating the boom, which leads to a reduction in work efficiency.

In view of the above problems, the present invention provides a work range display device for a boom work vehicle capable of displaying a margin work range from the current work range to a work range where boom operation should be restricted by an overload prevention device. It is intended to be provided.

B. Configuration of the Invention (Means for Solving the Problem) In order to achieve the above object, in the present invention, the actual load acting on the boom is detected by the actual load detecting means, and the limit which can be applied to the boom by the limit load calculating means is detected. Calculate the load,
Based on the difference between the actual load and the limit load, the margin work range calculation means calculates a margin work range that can be expanded from the current work range, and the margin work range is displayed by the display means. .

(Operation) In such a work range display device, based on the operating state of the boom at the present time, a limit load acts on the boom and the operating state in which the operation should be restricted by the overload prevention device, and at that time A limit range that can be reached by the tip end of is calculated, and the margin work range is calculated and displayed based on the horizontal distance from the limit end position of the boom to the calculated limit range.

(Embodiment) Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.

First, FIG. 1 shows an aerial work vehicle equipped with a work range display device according to the present invention.

A swivel base 3 is mounted on a vehicle body 2 of the aerial work vehicle 1, and the swivel base 3 is rotatable with respect to the vehicle body 2 by the operation of a swing motor (not shown). A base end of a boom 4 is pivotally attached to the upper part of the swivel base 3. This boom 4 has a tip boom 4b fitted in a base boom 4a, and can be hoisted and lowered by the operation of a hoisting cylinder mounted between the swivel 3 and the base boom 4b. The base boom 4a can be freely expanded and contracted by the operation of an expansion cylinder (not shown).

Further, a work bucket 6 is attached to the tip of the boom 4 (tip boom 4b). At the time of work, the boom 4 is hoisted by the hoisting cylinder 5 and the boom 4 is extended by the telescopic cylinder, so that the work bucket 6 is carried to a predetermined high place, and the work on the work bucket 6 is carried out at high places. . Since this aerial work vehicle 1 is used for electrical work, the tip boom 4b is formed of an insulating material, and the work bucket 6 and the base boom 4a are formed.
Insulation is provided between (that is, the vehicle body 2 and the ground) to prevent an electric shock accident of an operator who has boarded the work bucket 6.

Outriggers 8 are provided at four positions on the front, rear, left and right of the vehicle body 2. When the above work is performed, the outriggers 8 are projected laterally of the vehicle body 2 to a width corresponding to the work and are extended downward to support the vehicle body 2.

An overload prevention device 30 (see FIG. 2) is attached to the work vehicle 1 for high places. With this overload prevention device 30, the load (actual load W _A ) of the boom 4 acting in the falling direction of the vehicle body 2 due to the weight of the boom 4 and the weight of the work bucket 6 and the like can be supported by the outrigger 8 (limit load). (W _LMT ) is reached, the operation of the boom 4 in the direction of increasing the actual load W _A , that is, the lowering and extending operation of the boom 4 is further restricted.

The work range display device 20 shown in FIG. 2 is provided in combination with the overload prevention device 30.

The work range display device 20 includes a load sensor (actual load detection means) 21, a limit load calculation unit 22, a margin work range calculation unit 23, and a display unit 24.

The load sensor 21 detects an axial force acting on the hoisting cylinder 5 that supports the boom 4 and hoists the boom 4, that is, an actual load W _A that acts on the boom 4.

The limit load calculation unit 22 includes an undulation sensor 221 and an extension sensor 22.
2, a turning sensor 223, a tension sensor 224, and a limit load calculator 225. Undulation sensor 221, extension sensor
The turning sensor 222 and the turning sensor 223 detect the hoisting angle, the extension amount, and the turning angle (the turning angle of the turntable 3) of the boom 4, respectively. The tension sensor 224 detects the amount of extension of the outrigger 8 to the side of the vehicle body 2. When each outrigger 8 can independently set the stretch width, the stretch width sensor 224 is attached to each outrigger 8. The limit load calculator 225 is calculated from detection signals from the undulation sensor 221, the extension sensor 222, the turning sensor 223, and the tension sensor 224, that is, the turning position of the boom 4 and the working radius (the hoisting angle and length of the boom 4). ) And the stretch width of the outrigger 8, the load of the boom 4 that can be supported by the outrigger 8, that is, the limit load W.
Calculate _LMT .

Note that the actual load W _A detected by the load sensor 21 and the limit load W _LMT calculated by the limit load calculator 225
While the signal indicating is sent to the surplus work range calculator 23,
It is also sent to the overload prevention device 30 and used for controlling the operation regulation of the boom 4.

The surplus work range calculator 23 calculates the actual load W _A and the limit load W
_Due to the difference from _LMT , from the current tip position P _A of the boom 4 that produces the actual load W _A to the tip position of the boom 4 in the operating state that produces the limit load W _LMT (referred to as the regulation tip position P _LMT ). Calculate the horizontal distance L _H of. Specifically, for example, based on the detection signals from the undulation and extension sensors 221, 222, the calculated actual load W _A and the boom 4's own weight (stored in advance), the tip end load of the boom 4 (operation The own weight of the bucket 6 and the loaded weight) are calculated, and further, the boom 4 in an operating state in which the calculated limit load W _LMT is generated from the tip load of the boom 4 and the own weight of the boom 4.
The regulated leading end position P _LMT is calculated, and the above horizontal distance L _H is calculated from the current leading end position P _A and the regulated leading end position P _LMT .

This horizontal distance L _H is, in other words, a surplus work radius. By calculating this surplus work radius in each of the horizontal directions centering on the current tip position P _A of the boom 4, the boom 4
The difference between the working range where the operation of the
That is, the margin work range can be calculated.

The movable horizontal distance L _H of the tip of the boom 4 calculated by the surplus work range calculator 23 is a predetermined distance (display distance L _S
When the following occurs, the relevant signal is output by the E / O converter 4
The electric signal is converted into an optical signal by 1 and transmitted through the optical fiber cable 42 arranged along the boom 4, and further converted from the optical signal into an electric signal by the O / E converter 43, and the work bucket 6 Is sent to the display 24 attached to the. E / O converter 41, optical fiber cable 4
2 and the O / E converter 43 are used for maintaining the insulating state between the workbench 4 and the base end boom 4a.

As shown in FIG. 3, the display 24 has a screen 241 divided into four regions (front region I, left region II, and right region III) around the boom tip as front, rear, left, and right. It is possible to light up the display for each area. The distance L _S ′ from the center of the screen 241 to each side corresponds to the display distance L _S.

Next, the operation of the work range display device 20 is 012.

As a result of operating the boom 4 by the operation of the operator who has boarded the work bucket 6, as shown in FIG.
When the current front end position P _A of the display is located at the display distance L _S up to the regulated front end position P _LMT , the front area I of the display unit 24 shown in FIG. Is regulated when its tip position moves by the additional display distance L _S ,
It is recognized that the work bucket 6 cannot be moved forward any more. Also, when the regulated _{front end} position P _{LMT of} the boom 4 is located on the left and right of the current _{front end} position P _A , the left and right regions II and III are similarly turned on. This allows the operator to clearly and in advance determine the position to which the work bucket 6 can reach when the boom 4 is restricted, and the work bucket 6 can be held with the vehicle body 2 stopped at the current stop position. It is possible to immediately judge whether or not can move to the movement target position.

In the display 24, the screen 241 is divided into four areas centering on the tip position of the boom 4 and the display is performed in one area unit. However, each area is divided into unit areas. ,
As the tip end position of the boom 4 approaches the regulated tip end position P _LMT , the lights may be sequentially turned on.
You may display by numbers.

C. Effect of the Invention As described above, by using the work range display device of the present invention, from the current work range of the boom to the work range in the operating state in which the boom operation is restricted by the overload prevention device, The spare work range can be recognized by a concrete display. For this reason, when trying to move the boom tip to the target position, the boom tip should be moved to the target position if the stop position of the work vehicle is sufficient or the work vehicle itself should be moved. It is possible to make a clear decision before moving toward, and improve work efficiency.

[Brief description of drawings]

FIG. 1 is a rear elevational view of an aerial work vehicle equipped with a work range display device according to the present invention, FIG. 2 is a block diagram of the work range display device, and FIG. 3 is a view of the work range display device. It is a top view which shows a display. 1 …… Aerial work vehicle 4 …… Boom, 6 …… Work bucket 8 …… Outrigger W _A …… Actual load, W _LMT …… Limit load

Claims (1)

(57) [Scope of utility model registration request] 1. A boom work vehicle having at least an undulating and retractable boom, an actual load detecting means for detecting an actual load acting on the boom, and an operation of the boom for preventing an overloaded state of the boom. Based on the difference between the actual load detected by the actual load detection unit and the actual load detected by the actual load detection unit, A boom comprising: a margin work range calculation means for calculating a margin work range that can be expanded from the current work range of the boom; and a display means for displaying the margin work range calculated by the margin work range calculation means. Work range display for work vehicles.