JPH01133893A - Method and device for hanging load in crane - Google Patents

Abstract

PURPOSE: To prevent generation of vibration of a hoisted load in dynamic lift off by a crane, by moving a sheave on the top of a crane to the neighborhood of a vertical line passing through a center of gravity of the hoisted load according to a tilting angle detected by a tilting angle detecting device of a rope. CONSTITUTION: A tilting angle α or β in relation to a vertical line V is detected by a potentiometer 25, and displayed on a display device 27 via an arithmetic device 26. A boom 6 is hoisted by manually operating a changeover valve of a circuit to a hoisting derrick cylinder 5 of a telescopic boom 6 or the boom 6 is expanded or shrunk by manually operating a changeover valve to the telescopic cylinder of the boom 6, with diagonally looking display values on the display device 27, so that the tilting angle α or βbecomes zero. After a sheave 12 at the top of a fourth boom 10 is moved to the upper position of a center of gravity G of the hoisted load 15, that is, a rope 13 is moved to the neighborhood of a vertical line V passing through the center of gravity G of the hoisted load 15, a winch winds the rope 13, the hoisted load 15 is hoisted along the vertical line V and is provided with dynamic lift, off without vibration of the hoisted load 15 to perform cargo handling operation.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method and device for hoisting loads in a crane.

(Prior art) Conventional cranes include those shown in Figure 5 (for example, see the hydraulic truck crane KATONK-450B catalog published by Kato Seisakusho Co., Ltd.).
.

This crane truck 1 is provided with a telescopic boom 6 which is operated to raise and lower by a derrick cylinder 5 on a rotating part 3 on a vehicle body 2 of the crane truck 1, and the telescopic boom 6 is attached to the outermost side with its base pivoted to the rotating part 3. (First) Inside the boom 7, there is a second boom 7 that is extendable and retractable by an extendable means (not shown) such as a hydraulic cylinder.
Boom 8, third boom 9, and fourth (innermost) boom 1
0, by means of a hook block 14 at the end of the rope 13 hanging from the sheave 12 at the top of the innermost boom 10 of the telescopic boom 6.
The target hanging load 15 is suspended and handled.

Although not shown in the catalog, information on the lifting angle of the telescopic boom, cargo handling radius information, limit load information,
It is also described that actual load information, maximum hook lifting height information, etc. are processed by a calculation device and numerically displayed at an appropriate place in the operator's cabin, and the crane is operated with reference to the displayed values, and the telescopic boom is It is also described that an undulating or non-undulating, telescopic or non-retractable jib is provided around the top of the innermost boom 10 of No. 6, and a rope having a hook block at the end is suspended from a sheave at the top of the jib. ing.

(Problems to be solved by the invention) However, in such conventional cranes,
A book block 14 is suspended via a rope 13 from a sheave 12 at the top of the innermost boom 10 of the telescopic boom 6 and/or a sheave at the top of the jib provided around the top.
When starting the cargo handling operation for the target suspended load 15, first, place the sheave 12 at the top of the innermost boom 10 of the telescopic boom 6 or the sheave at the top of the jib above the suspended load 15 to be operated. After that, the hook block 14 at the end of the rope 13 is engaged with the suspended load 15 for cargo handling operation. Since this was normally determined by visual inspection by the operator, the vertical line passing through the center of gravity G of both sheaves 12 and the suspended load 15 is often misaligned, especially when the telescopic boom 6 of a large crane is When the long boom is extended, the top sheave 12
It is extremely difficult to match the vertical line passing through the center of gravity G of the hanging load 15 accurately by visual inspection.

Then, when the load lifting operation is started in a state where the top of the innermost boom 10 of the telescopic boom 6 and/or the sheave 12 at the top of the jib is deviated from the vertical line passing through the center of gravity G of the suspended load 15,
At the same time as the suspended load 15 "cuts off the ground" (the suspended load 15 rises from the mounting surface by the hook block 14 at the lower end of the rope 13), the lifted load 15 moves toward the chain line position 15A directly below the sheave 12. The suspended load 15 moves between the solid line position 15 and the chain line position 15B due to inertia and reaches the chain line position 15B on the left side (FIG. 5).
This is caused by temporary reciprocating vibration around the sheave 12, and conventionally, even if such vibration occurred,
There was a problem in that it was necessary to secure a large space around the crane truck 1 in order to prevent danger to the area around the crane.

In addition, when the telescopic boom 6 of the crane and/or the jib starts loading and unloading the suspended load 15, the telescopic boom 6
And/or a corresponding deflection occurs in the jib due to the lifting of the suspended load 15, and this deflection is also one of the causes of vibration of the suspended load 15 due to the misalignment between the center of gravity G of the suspended load 15 and the sheave 12. However, in order to simplify the explanation, a more detailed explanation of the influence of this deflection will be omitted here.

However, the problem mentioned above is that the operator of the crane can adjust the various parts slowly based on the visual confirmation of the various displayed values, so that the vibration can be reduced to a relatively small level.
However, the adjustment is troublesome and requires a relatively long time, and there are problems in that it is not easy to eliminate the vibration of the suspended load due to the delay in adjustment.

In view of such conventional examples, the present invention has been developed by engaging the lower end of a rope suspended from a sheave at the top of a crane with a suspended load, and then adjusting the inclination angle between the rope and a vertical line passing through the center of gravity of the suspended load. After that, the sheave at the top of the crane is moved around the vertical line passing through the center of gravity of the suspended load so as to eliminate the detected inclination angle, and then the crane is moved to remove the suspended load from the ground. This is a load lifting method, and in order to carry out this method, a hook block is suspended from a sheave at the top of the crane via a rope, and the hook block is engaged with the rope around the sheave shaft, and the rope and the crane are A device is provided to detect an inclination angle with a vertical line passing through the center of gravity of the suspended load, and the sheave at the top of the crane can be moved to the vertical line passing through the center of gravity of the suspended load based on the detected value. Therefore, it is an object of the present invention to provide a method and device for hoisting loads in a crane that does not have the above-mentioned problems.

(Means for Solving the Problems) In order to solve the above-mentioned problems of the conventional art, the present invention aims to solve the above-mentioned problems by engaging the lower end of the rope suspended from the sheave at the top of the crane with the suspended load. and a vertical line passing through the center of gravity of the suspended load, and then move the sheave at the top of the crane around the vertical line passing through the center of gravity of the suspended load so as to correspond to the detected angle of inclination. move, then
A crane load lifting method that cuts the suspended load to the ground,
In addition, a hook block is suspended from a sheave at the top of the crane via a rope, and is engaged with the rope around the sheave shaft, so that a vertical line passing through the rope and the center of gravity of the suspended load suspended from the crane is connected. a detection device for detecting the inclination angle of the rope, and means for moving the sheave at the top of the crane to a vertical position passing through the center of gravity of the suspended load in accordance with the inclination angle detected by the rope inclination angle detection device. It is prepared.

(Function) Since the present invention has the above-described configuration, the hook block hanging down from the sheave at the top of the crane via the rope is suspended by the crane before the start of the load lifting work by the crane. The inclination angle with respect to the vertical line passing through the center of gravity of the load is detected by a detecting device for detecting the inclination angle with respect to the vertical line of the rope suspended around the sheave shaft and engaged with the rope, and the inclination angle detected by the device Accordingly, the sheave at the top of the crane is moved and adjusted so as to eliminate the inclination angle, and the sheave is placed around the vertical line passing through the center of gravity of the suspended load, and then vibration of the suspended load does not occur. Start the load lifting operation.

(Embodiment) Hereinafter, an embodiment of the method and apparatus for hoisting a load in a crane according to the present invention will be described with reference to FIGS. 1 to 3. Note that the same names and symbols are used for parts common to the conventional example shown in FIG. 5.

In the figure, 1 is a crane truck, 2 is a car body, 3 is a rotating part on the car body, 4 is an outrigger, 5 is a derrick cylinder, 6 is a telescopic boom, the base of which is rotatably supported by the rotating part 3, The first (outermost) boom = 8-7 is raised and lowered by a derrick cylinder 5, and the first boom 7 is slidably inserted into the first boom 7 and is expanded and contracted by an appropriate expansion and contraction means such as a hydraulic cylinder and a rope (not shown). The second boom 8, third boom 9, and fourth (innermost) boom 10 that are operated constitute a four-stage telescopic boom. 11 is a shaft supporting the sheave 12 on the top of the fourth boom 8; 13 is a rope; 14 is a hook block;
5 is a hanging load.

Reference numeral 20 denotes a detection device for detecting inclination angles α, β, etc. of the rope 13 with respect to a vertical line V passing through the center of gravity G of the hanging load 15. The rope 1 is attached to one side of the lower part of the support leg 22, which is pivotably attached to the support leg 22.
3, and a balance weight 24 with the guide roller 23.23 on the other side. 24, the device 20 is always suspended directly below the end 21 of the shaft 11 unless an external force is applied to the device 20. 25 is a potentiometer 26 provided at the base of the supporting leg 22 to detect the inclination angle α or β of the supporting leg 22 with respect to the vertical line V;
2 is an arithmetic unit, and 27 is a tilt angle display device.

Next, the operation of this embodiment will be explained.

First, move the crane truck 1 to the target cargo handling location,
After the vehicle body is supported in a predetermined position by the outrigger 4, the hook block 14 is suspended from the sheave 12 at the top of the fourth boom 10 of the telescopic boom 6 via the rope 13,
A hanging load 15 is suspended by the hook block 14. Then,
While winding the rope 13 with a winch (not shown),
It is similar to conventional similar cranes in that the hoisted load 15 is handled by raising and lowering the telescopic boom 6 using the derrick cylinder 5, but in this embodiment, at the start of the cargo handling operation, a winch (not shown) is used. rope 13
When the rope 13 is wound up, the sheave 1
2 is on the left side (12A in FIG. 2) or the right side (12B in the same figure) of the vertical line V passing through the center of gravity G of the suspended load 15, the relationship between the roller 23.23 and the rope 13 is determined. As a result, the supporting leg 22 of the detection device 20 swings clockwise or counterclockwise around the end 21 of the sheave 12 shaft 11.
The inclination angle detection device 20 of the rope 13 detects the angle α or β with respect to the line passing through the center of gravity G of the suspended load 15, and uses the potentiometer 25 at the base of the supporting leg 22 to detect the angle α or β of the rope 13.
The potentiometer 2 rotates clockwise or counterclockwise around the shaft 21A or 21B in the same direction as the chain line position 13A or 13B of No. 3, and its inclination angle α or β with respect to the vertical line V is
5 is detected by the display device 27 via the arithmetic device 26.
will be displayed.

Then, while looking at the displayed value on the display device 27, the operator switches the pressure oil supply and discharge circuit to the luffing derrick cylinder 5 of the telescopic boom 6 so that the inclination angle α or β becomes 0. The hoisting boom 6 is raised or lowered by manually operating a valve (not shown), or the telescopic boom 6 is extended or contracted by manually operating a pressure oil supply/discharge switching valve (not shown) to the telescopic cylinder of the telescopic boom 6. As a result, the sheave 17 at the top of the fourth boom 10 is positioned above the center of gravity G of the suspended load 15, that is, the rope 13 is placed at the 7th position on the vertical line passing through the center of gravity G of the suspended load 15, and then the rope 13 is reeled in using a winch (not shown). , the suspended load 15 is hoisted along the vertical line {circle around (2)}, the suspended load 15 is cut off the ground without vibrating, and the cargo handling operation is thereafter carried out in the same manner as a normal crane.

In addition, the arithmetic unit 26 is activated by a change in the output of the potentiometer 25 on the sheave shaft 11 end 21 in response to clockwise or counterclockwise rotation of the tilt angle detecting device 20 around the shaft 11 end 21. via the derrick cylinder 5 to control the supply and discharge of pressure oil to the derrick cylinder 5 to adjust the up-and-down angle of the telescopic boom 6, or the telescopic cylinder (not shown) of the telescopic boom 6.
By controlling the supply and discharge of pressure oil to and from the telescopic boom, the length of the telescopic boom is adjusted, and the sheave 12 at the top of the fourth boom 10 is
After moving the rope 13 to the 7th position on the vertical line passing through the center of gravity of the load 15 and positioning the rope 13 on the ship's line V, the rope 13 is reeled in by a winch (not shown), and the suspended load 15 is hoisted along the vertical line V passing through the center of gravity G. , the suspended load 15 is cut off the ground without vibrating, and thereafter the cargo handling operation is carried out in the same manner as described above.

Although not shown, the innermost boom 10 of the telescopic boom 6
Regarding a crane that has a telescopic or non-retractable jib installed around the boom head at the top so that it does not rise or fall, and that handles a suspended load 15 using a hook block at the end of a rope hanging from a sheave at the top of the jib. Also, the above-mentioned figures 1 to 3 are attached to the sheave shaft at the top of the jib.
By rotatably providing an inclination angle detection device having the same structure as the inclination angle detection device 20 of the rope 13 shown in the figure, and by engaging the guide roller 23 with the rope 13,
By detecting and displaying the inclination angle of the rope 13 at the initial stage of the cargo handling operation of the suspended load 15 suspended from the sheave at the top of the jib, and using the displayed value, the same cargo handling operation as described above can be performed.

Next, another embodiment of the invention will be described with reference to FIG. Note that the same names and symbols are used for parts common to those of the embodiment illustrated in FIGS. 1 to 3.

In this embodiment, the fourth (innermost) boom 1 of the telescopic boom 6
A sheave 17 is provided on the boom head 16 at the top of the boom head 16, and an inclination angle detection device 20 for the rope 18 is provided at the end 21 of the sheave shaft 11.
The base of the support leg 22 is rotatably attached to the base of the rope 1.
8 is brought into contact with the guide roller 23.23 at the lower end of the support leg 22 of the inclination angle detection device 20, and the inclination angle is displayed via the calculation device 26 by a potentiometer (see 25 in FIG. 3) provided at the base thereof. While displaying on the device (27), controlling the supply and discharge of pressure oil to the derrick cylinder 5 through the same calculation device 26 to raise and lower the telescopic boom 6,
The sheave 17 at the top of the fourth boom 1o is moved to match the 7th vertical line passing through the center of gravity G of the suspended load 15, and the rest of the structure and operation are almost the same as in the previous embodiment. be.

Although not shown, the guide roller 23 of the inclination angle detection device 20 of the rope 13 shown in FIGS.
Instead of the guide roller 23, a ring-shaped or cylindrical guide member that is guided by the rope 13 and swings together with the rope 13 may be disposed at a position corresponding to the guide roller 23.23. The structure of the guide part is not only ring-shaped or cylindrical and extremely simple, but also its weight can be reduced.
By reducing the weight of the rope 1 with respect to the vertical line V,
The inclination angle detection device 20 of No. 3 can be configured to be lightweight and has good responsiveness.

Although not shown, the inclination angle detection device 20 of the rope 13 is rotatably supported around a sheave shaft on a trolley that runs along a horizontal beam of a so-called tower crane, and is mounted on the lower part of its supporting leg. By engaging the guide roller with the rope hanging from the sheave, when the hook block at the lower end of the rope hanging from the sheave is locked to the hanging load 15, the center of gravity G of the rope and the hanging load 15 can be determined. It can also be used as a device for detecting the inclination angle with respect to the vertical line V passing through.

(Effects of the Invention) Since the present invention has the configuration and operates as described above, the following effects can be obtained.

(1) Detecting the inclination angle of the rope hanging from the sheave with respect to the vertical line around the sheave shaft at the top of the crane,
In accordance with the detected value, move the sheave at the top of the crane around the vertical line passing through the center of gravity of the suspended load, and then
Since this starts the load lifting operation, it is possible to prevent the vibration of the suspended load when the crane is used to cut the ground.

(2) At the beginning of cargo handling work, the positional deviation between the vertical line passing through the center of gravity of the suspended load and the sheave at the top of the crane is detected by the rope inclination angle detection device, and the detected value is used to determine the position of the suspended load. Since the sheave position at the top of the boom can be adjusted prior to cutting, vibrations can be prevented from occurring at the start of lifting the load.

(3) The inclination angle detection device of the cargo handling rope consists of a guide with a balance weight installed at the bottom of the supporting leg that hangs rotatably from the sheave shaft at the top of the boom and/or the jib, so it is possible to detect the tilting of the cargo handling rope. It is possible to configure a detection means with a simple structure that has good followability for the following.

(4) A rope inclination angle detection device is installed around the sheave shaft at the top of the crane, and after the device moves the sheave at the top of the crane around the vertical line passing through the center of gravity of the lifted load, By starting the crane, the cause of the reciprocating vibration of the suspended load at the beginning of the same load lifting is eliminated, so there is no need to secure a large space around the crane as a measure to prevent the occurrence of danger due to such vibration.

The inclination angle detection device of the rope with respect to the vertical line automatically controls the supply and discharge of pressure oil to the boom hoisting derrick cylinder of the crane, or automatically controls the extension and retraction means of the telescoping boom of the crane. If the sheave can be moved around the vertical line by controlling expansion and contraction, the sheave at the top of the crane and the vertical line passing through the center of gravity of the suspended load can be automatically aligned.

The rope inclination angle detection device is composed of a guide disposed on one side of a lower leg rotatably suspended from a sheave shaft at the top of the crane such as the boom and/or jib, and a balance weight thereof. In this way, it is possible to easily construct an inclination angle detection device that can easily follow the rope.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a schematic structure of a preferred embodiment for carrying out the method for lifting a suspended load in a crane according to the present invention, FIG. 2 is an explanatory diagram of its operation, and FIG. −
FIG. 4 is a side view of a main part of another embodiment, and FIG. 5 is an explanatory view of the operation of a conventional example. 1... Crane truck, 5... Derrick cylinder, 6...
Telescopic boom, 10... Fourth (innermost) boom,
11... shaft, 12.17... sheave,
13.18...rope, 14.19...
...Hook block, 15...Ionization 20...
... Tilt angle detection device, 22 ... Support leg, 2
3... Guide roller, 25... Potentiometer, G...
Center of gravity,■・・・・・・Plumb line.

Claims (4)

[Claims] (1) After the lower end of the rope suspended from the sheave at the top of the crane is engaged with the suspended load, the inclination angle between the rope and a vertical line passing through the center of gravity of the suspended load is detected, and then the detected angle is detected. A method for hoisting a load from a crane, which comprises moving a sheave at the top of the crane around a vertical line passing through the center of gravity of the hoisted load to correspond to the inclination angle, and then cutting off the hoisted load. (2) A hook block is suspended from a sheave at the top of the crane via a rope, and a vertical line that engages with the rope around the sheave axis and passes through the rope and the center of gravity of the suspended load suspended from the crane. means for moving the sheave at the top of the crane to a vertical line passing through the center of gravity of the suspended load in accordance with the inclination angle detected by the rope inclination angle detection device; A load lifting device for a crane, characterized by comprising: (3) The sheave is moved around the vertical position by controlling the supply and discharge of pressure oil to the boom hoisting derrick cylinder of the crane using the inclination angle detection device of the rope with respect to the vertical line. A load lifting device for a crane according to claim 2, characterized in that: (4) The sheave is moved around the vertical line by controlling the extension/contraction means of the boom of the crane to extend/contract using the inclination angle detection device of the rope with respect to the vertical line. A load lifting device for a crane according to claim 2.