JP2021020771A - Derricking/winding control system of jib crane - Google Patents

Abstract

To provide a derricking/winding control system of a jib crane capable of selecting a derricking motor with a minimum required power output and capable of improving cargo handling efficiency.SOLUTION: A derricking/winding control system of a jib crane comprises a control device which makes a derricking motor bear a horizontal acceleration β only by driving a winding motor to cancel a vertical upward acceleration α acting on a suspended load 7A when pulling in the suspended load 7A by the standing-up movement of a jib.SELECTED DRAWING: Figure 2

Description

The present invention relates to an undulating hoisting control system for a jib crane.

Generally, various jib cranes are used for the construction of structures such as high-rise buildings or the construction of ships in shipbuilding docks.

FIG. 6 shows an example of a climbing crane 1A as a jib crane 1. The climbing crane 1A is a mast installed on a floor plate inside a structure and as a support portion capable of sequentially adding a mast block 2a upward. It has 2. A swivel body 4 is rotatably arranged on the top of the mast 2 via an elevating unit 3 that can be raised and lowered along the mast 2. A jib 5 is undulatingly attached to the swivel body 4, and a counter frame 6 extending rearward is integrally provided on the swivel body 4. On the counter frame 6, a hoisting drum 9 for hoisting and lowering a hoisting wire rope 8 for suspending a hanger 7 for a suspended load 7A from the tip of the jib 5 and a hoisting wire rope 10 for the jib 5 are wound. An undulating drum 11 for raising and lowering is installed. Further, the swivel body 4 is provided with a guy support 12, and a sheave 13 on which a hoisting wire rope 8 unwound from the hoisting drum 9 is hung and a sheave 13 and the undulating drum are mounted on the top of the guy support 12. A sheave 14 on which the undulating wire rope 10 unwound from 11 is hung is arranged. Further, a sheave 15 on which the hoisting wire rope 8 is hung is arranged at the tip of the jib 5.

As a general technical level related to the climbing crane 1A as described above, for example, Patent Document 1 is available.

In the case of the jib crane 1, if the jib 5 is simply undulated, the height of the suspended load 7A may fluctuate, which may affect workability.

For this reason, there is a conventional jib crane 1 provided with a horizontal pull-in mechanism called a rope balance type as a method for suppressing fluctuations in the height of the suspended load 7A when the jib 5 is undulating (for example,). See Patent Document 2).

However, in the rope-balanced jib crane 1, the number of sheaves 13 and 15 on which the hoisting wire rope 8 is hung becomes very large, and the length of the hoisting wire rope 8 becomes extremely long.

In order to solve such a problem, a jib crane 1 provided with a horizontal pull-in mechanism called a drum balance type has been developed.

In the case of the conventional drum-balanced jib crane 1, as shown in FIG. 7, the hoisting wire rope 8 unwound from the hoisting drum 9 is hung around the sheave 13a at the top of the guy support 12 (see FIG. 6). After that, the load detector 20 for detecting the tension acting on the hoisting wire rope 8 is hung on the sheave 13b to which the load detector 20 is attached, and further, the sheave 13c at the top of the guy support 12 and the sheave 15a at the tip of the jib 5 The sheave 7b that suspends the sheave 7a of the hanger 7, the sheave 15b at the tip of the jib 5, and the sheave 13d at the top of the guy support 12 are sequentially hung around and wound around the undulating drum 11.

The hoisting wire rope 8 unwound from the hoisting drum 9 has two left and right systems, and the load detector 20 is not provided on the sheave 13b of the right system shown in FIG. 7.

Further, the undulating wire ropes 10 unwound from the two undulating drums 11 on the left and right are attached to the sheave 14a at the top of the guy support 12 and the undulating pendant sheave block 16 connected to the tip of the jib 5 via the undulating pendant rope 10a, respectively. The sheave 14b, the sheave 14c at the top of the guy support 12, the sheave 14d attached to the undulating pendant sheave block 16, and the sheave 14e attached to the undulating swing sheave block 17 protruding from the top of the guy support 12 are sequentially hung. , It is in a form that can be connected.

JP-A-2017-178502 Japanese Unexamined Patent Publication No. 52-47258

By the way, even in the case of the drum balance type or rope balance type jib crane 1, as shown in FIG. 2, when the suspension load 7A is pulled in by standing the jib 5 from the laid down state, the hanger 7 is high. Although the fluctuation is smaller than that of the jib crane 1 without the horizontal pull-in mechanism, it is unavoidable.

The undulating motor that drives the undulating drum 11 also bears the power to pull the suspended load 7A upward when the suspended load 7A is pulled in by the standing operation of the jib 5, which wastes torque. There is.

For this reason, in the case of the conventional jib crane 1, a large undulation motor that includes torque that is originally wasted has to be selected.

On the other hand, the smaller the undulation angle of the jib 5 (closer to horizontal), the greater the undulation tension acting on the undulation wire rope 10 and the torque of the undulation motor, and the larger the undulation angle of the jib 5 (vertically). The closer it is), the smaller the undulating tension acting on the undulating wire rope 10, and the smaller the torque of the undulating motor. The hoisting tension acting on the hoisting wire rope 8 is constant regardless of the undulation angle of the jib 5 for the same suspended load 7A.

However, the rotation speed of the undulation motor that drives the undulation drum 11 is constant regardless of the undulation angle of the jib 5.

Here, if the torque of the undulation motor is small, it is possible to increase the rotation speed of the undulation motor and shorten the undulation time. However, in the case of the conventional jib crane 1, the undulation motor corresponds to the undulation angle of the jib 5. The rotation speed of the motor was not increased, leaving room for improvement in cargo handling efficiency.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide an undulation hoisting control system for a jib crane capable of selecting an undulation motor having a minimum required output and improving cargo handling efficiency. It is a thing.

The present invention includes a jib that is undulating and undulating.
An undulating drum that winds up and downs an undulating wire rope that undulates the jib,
An undulation motor that drives the undulation drum,
An undulation inverter that controls the rotation speed of the undulation motor,
A hoisting drum for hoisting and lowering a hoisting wire rope for hanging a hanger for hanging from the tip of the jib,
A hoisting motor that drives the hoisting drum,
A hoisting inverter that controls the rotation speed of the hoisting motor,
A control device that causes the undulation motor to bear only the horizontal acceleration by driving the hoisting motor so as to cancel the vertical upward acceleration acting on the suspended load when the suspended load is pulled in by the standing operation of the jib. It relates to the undulation hoisting control system of the equipped jib crane.

In the undulation hoisting control system of the jib crane, the control device can calculate the torque of the undulation motor based on the output current of the undulation inverter and select the rotation speed of the undulation motor from the rated output diagram.

Further, the control device can calculate the torque of the hoisting motor based on the output current of the hoisting inverter and select the rotation speed of the hoisting motor from the rated output diagram.

According to the undulation hoisting control system of the jib crane of the present invention, an undulation motor having the minimum required output can be selected, and an excellent effect of improving cargo handling efficiency can be obtained.

It is a control block diagram which shows the Example of the undulating hoisting control system of the jib crane of this invention. It is a diagram which shows the locus of the hanger (suspension load) at the time of jib standing in the Example of the undulation hoisting control system of the jib crane of this invention. It is a rated output diagram which shows the relationship between the rotation speed and torque of the undulation motor in the Example of the undulation hoisting control system of the jib crane of this invention. It is a rated output diagram which shows the relationship between the rotational speed and torque of a hoisting motor in the Example of the undulating hoisting control system of the jib crane of this invention. It is a flowchart which shows the Example of the undulation hoisting control system of the jib crane of this invention. It is a schematic block diagram which shows an example of a general jib crane (climbing crane). It is a perspective view which shows an example of how to hang a hoisting wire rope in a conventional drum balance type jib crane.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 to 5 are examples of the undulation hoisting control system of the jib crane of the present invention, and the parts having the same reference numerals as those in FIGS. 6 and 7 in the drawings represent the same objects.

As shown in FIG. 1, the hoisting drum 9, the hoist motor 9A is driven through the winding speed reducer 9B, the rotational speed N _HM of the hoist motor 9A, the controller 30 (PLC: Programmable Logic Controller) It is controlled by the hoisting inverter 9C connected to. Incidentally, the on hoist motor 9A, the rotational speed sensor 9D such as an encoder for measuring the rotational speed N _HM is attached, the rotational speed N _HM measured by the rotational speed sensor 9D is inputted to the control unit 30 It has become so.

Also, undulating drum 11, the undulations motor 11A is driven through the contoured speed reducer 11B, the rotational speed N _LM of the undulations motor 11A is adapted to be controlled by a connected undulating inverter 11C to the controller 30 ing.

A jib angle sensor 40 for measuring the undulation angle of the jib 5 is connected to the control device 30. Further, the actuator 50 and the display 60 in the driver's cab are also connected to the control device 30.

Then, in the case of the present embodiment, the control device 30 winds up so as to cancel the vertical upward acceleration α (see FIG. 2) acting on the suspended load 7A when the suspended load 7A is pulled in by the standing operation of the jib 5. By driving the motor 9A, only the horizontal acceleration β (see FIG. 2) is borne by the undulating motor 11A.

Further, the control device 30, so as to select the rotational speed N _LM undulations motor 11A from the rated output diagram and calculates the torque T _LM undulations motor 11A based on the output current of the relief inverter 11C (see FIG. 3) It has become.

Furthermore, the control device 30, the rotational speed N _HM the hoist motor 9A from rated output diagram and calculates the torque T _HM of hoist motor 9A on the basis of the output current (see FIG. 4) of the hoist inverter 9C Is to be selected.

Next, the operation of the above-described embodiment will be described.

First, when the undulation of the jib 5 is started and the suspended load 7A is pulled in (see step S100 in FIG. 5), the output current of the undulation inverter 11C is measured by the control device 30 (see step S110 in FIG. 5). The torque T _LM of the undulation motor 11A is calculated (see step S120 in FIG. 5), and the rotation speed N _LM of the undulation motor 11A is selected (see step S130 in FIG. 5).

Here, the rotational speed N _LM of the undulating motor 11A has the fastest value corresponding to the torque T _LM of the undulating motor 11A calculated by the control device 30 based on the output current of the undulating inverter 11C, which is the rated output shown in FIG. Obtained from the diagram. In the case of the drum balance type jib crane 1, the undulating wire rope 10 and the hoisting wire rope 8 are wound around the undulating drum 11 as shown in FIG. Therefore, tension _{W L} undulations wire rope 10, the tension of the _{W H} of hoisting wire ropes 8, when the pitch circle diameter of the undulating drum 11 (multilayer winding drum) and PCD, the torque _{T LD} undulations drum 11 T _{It is obtained from LD} = (W _{L- WH} ) × PCD / 2, and the torque T _LM of the undulation motor 11A can be converted from this value. Furthermore, if the output of the undulations motor 11A was _{P LM,} fastest value on the rotational speed _{N LM} theory undulations motor 11A _can also be obtained from _{N LM = P LM / T LM} .

Wherein at the time of the suspended load 7A retraction of the output current of the hoisting inverter 9C also measured by the control unit 30 (see step S140 in FIG. 5), the torque _{T HM} of hoist motor 9A is calculated (see step S150 in FIG. 5) , the rotational speed _{N HM} hoist motor 9A is selected (see step S160 in FIG. 5).

Here, the rotational speed N _HM of the hoist motor 9A is fastest value commensurate with the torque T _HM of hoist motor 9A calculated by the control unit 30 based on the output current of the hoisting inverter 9C is 5 Obtained from the rated output diagram shown.

Subsequently, when the derricking angle of the jib 5 changes (see step S170 in FIG. 5), tension _{W L} undulating wire rope 10 is changed (see step S180 in FIG. 5).

The tension _{W L} of the hoisting wire rope 10 is changed, the torque _{T LD} undulating drum 11 is changed (see step S190 in FIG. 5), the torque _{T LM} undulations motor 11A also changes (see step S200 in FIG. 5) ..

After that, it is determined whether or not the undulation of the jib 5 has been stopped (see step S210 in FIG. 5), and if it has not been stopped, the process returns to step S110 and the same operation as described above is repeated.

In the case of this embodiment, the undulation motor 11A is driven at a rotation speed N _LM which is the fastest value corresponding to the torque T _LM of the undulation motor 11A calculated by the control device 30 based on the output current of the undulation inverter 11C. standing movements of the jib 5 of the hoisting motor 9A is driven at a rotational speed N _HM as the fastest value commensurate with the torque T _HM of hoist motor 9A calculated by the control unit 30 based on the output current of the hoisting inverter 9C When the suspended load 7A is pulled in, the vertical upward acceleration α (see FIG. 2) acting on the suspended load 7A is canceled by the drive of the hoisting motor 9A, and only the horizontal acceleration β (see FIG. 2) undulates. It will be borne by the motor 11A.

That is, relief motor 11A for driving the undulating drum 11, upon retraction of the suspended load 7A by standing movements of the jib 5, you do not have to bear the power suspended load 7A is pulled upward, wastefully consuming torque T _LM It disappears.

Therefore, in the case of the jib crane 1 of the present embodiment, it is possible to select a small undulating motor 11A that does not include the wasted torque _TLM .

On the other hand, as the relief angle of the jib 5 is small (close to horizontal), relief tension acting on the hoisting wire ropes 10 are also increased torque T _LM undulations motor 11A increased, also, a large derricking angle of the jib 5 (nearly vertical) as undulation tension acting on the hoisting wire ropes 10 are also small torque T _LM undulations motor 11A becomes small, in this embodiment, the control device on the basis of the output current of the undulations inverter 11C The undulation motor 11A is driven at a rotation speed N _LM which is the fastest value corresponding to the torque T _LM of the undulation motor 11A calculated in 30. Therefore, when the torque T _LM of the undulation motor 11A is small, the rotation speed N _LM of the undulation motor 11A is increased and the undulation time is shortened, so that the cargo handling efficiency can be improved as compared with the conventional jib crane 1.

In this way, the undulating motor 11A having the minimum required output can be selected, and the cargo handling efficiency can be improved.

Then, in the case of this embodiment, the control device 30 calculates the torque T _LM of the undulation motor 11A based on the output current of the undulation inverter 11C, and selects the rotation speed N _LM of the undulation motor 11A from the rated output diagram. It has become like. With this configuration, the undulation motor 11A can be driven at a rotation speed N _LM that is the fastest value corresponding to the torque T _LM of the undulation motor 11A calculated by the control device 30 based on the output current of the undulation inverter 11C, and the cargo handling efficiency. It is effective in increasing.

In the case of this embodiment, the control device 30, the rotational speed N _HM the hoist motor 9A from rated output diagram and calculates the torque T _HM of hoist motor 9A on the basis of the output current of the hoisting inverter 9C Is to be selected. With such a configuration, it drives the winding motor 9A at a rotational speed N _HM as the fastest value commensurate with the torque T _HM of hoist motor 9A calculated by the control unit 30 based on the output current of the hoisting inverter 9C , It is effective in improving cargo handling efficiency.

The undulation hoisting control system for the jib crane of the present invention is not limited to the above-described embodiment, and can be applied to a jib crane without a horizontal retracting mechanism, a rope-balanced jib crane, and the like. Of course, various changes can be made without departing from the gist of the invention.

1 Jib crane 1A Climbing crane 2 Mast 2a Mast block 3 Lifting unit 4 Swivel body 5 Jib 6 Counter frame 7 Hanger 7A Suspended load 7a Sheave 7b Sheave 8 Hoisting wire rope 9 Hoisting drum 9A Hoisting motor 9B Hoisting reducer 9C Winding Inverter 9D Rotation Speed Sensor 10 Undulating Wire Rope 10a Undulating Pendant Rope 11 Undulating Drum 11A Undulating Motor 11B Undulating Reducer 11C Undulating Reducer 12 Guy Support 13 Sheave 13a Sheave 13b Sheave 13c Sheave 13d Sheave 14 Sheave 14a Sheave 14 Sheave 14e Sheave 15 Sheave 15a Sheave 15b Sheave 16 Undulating Pendant Sheave Block 17 Undulating Swing Sheave Block 20 Load Detector 30 Control Device 40 Jib Angle Sensor 50 Operator 60 Indicator α Acceleration β Acceleration

Claims (3)

Jibs that are undulating and undulating,
An undulating drum that winds up and downs an undulating wire rope that undulates the jib,
An undulation motor that drives the undulation drum,
An undulation inverter that controls the rotation speed of the undulation motor,
A hoisting drum for hoisting and lowering a hoisting wire rope for hanging a hanger for hanging from the tip of the jib,
A hoisting motor that drives the hoisting drum,
A hoisting inverter that controls the rotation speed of the hoisting motor,
A control device that causes the undulation motor to bear only the horizontal acceleration by driving the hoisting motor so as to cancel the vertical upward acceleration acting on the suspended load when the suspended load is pulled in by the standing operation of the jib. Equipped jib crane undulation hoisting control system. The undulation hoisting control system for a jib crane according to claim 1, wherein the control device calculates the torque of the undulation motor based on the output current of the undulation inverter and selects the rotation speed of the undulation motor from the rated output diagram. The undulating hoisting control system for a jib crane according to claim 2, wherein the control device calculates the torque of the hoisting motor based on the output current of the hoisting inverter and selects the rotation speed of the hoisting motor from the rated output diagram.

Images