JPH08324960A - Crane bracing control method - Google Patents

Abstract

PURPOSE: To realize high accurate bracing control by reducing a cost further with low space, by closing a notch circuit when started by prescribed timing after opening a start to perform bracing, and performing bracing by closing a reverse notch and by a mechanical brake when stopped. CONSTITUTION: In a transverse control system, a controller 21 able to actuate an operating handle is set up in a transverse controller 20 of an existing direct control system, to perform control by rotating an operating handle with a servomotor based on a command from a control panel 22. Since a brake is not provided in transverse control, a reverse notch is used in braking similarly to labor. That is, in transverse bracing control, first during the time from starting acceleration to a fixed speed, a notch is closed to be matched with swing. Here is closed the notch by timing of surely suppressing the swing. In a deceleration method, the reverse notch is closed so as to negate each other energy swung with braking the first step reverse notch by the second step reverse notch. Timing of closing is performed, for instance, by a swing feedback.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crane steadying control method in an automatic operation method for traversing and traveling of a suspended wire crane which has a notch circuit and does not have variable speed control such as an inverter.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication (Kokai) No. 1-281293 discloses that, while hoisting or lowering a rope for suspending a load when operating a suspension crane, the crane is run to steady a suspended load. During acceleration, acceleration-deceleration-
There is disclosed a method of performing steady rest by repeating a plurality of traveling patterns of acceleration and deceleration-acceleration-deceleration during deceleration.

Japanese Patent Laid-Open No. 1-281294 discloses a target speed and an allowable acceleration / deceleration speed during traveling and traversing, a target hoisting or lowering speed, a wire length at the time of starting traveling and traversing, and a hanging speed. Based on the position of the center of gravity of the load,
A steady rest control method for calculating an operation pattern by calculating a phase trajectory is disclosed.

[0004]

However, all of the above-described steady rest control methods are technologies based on the assumption that variable speed control is performed by converting the motor circuit into an inverter. That is, when steadying is performed using the above method, in order to realize the calculated operation pattern with high accuracy, it is necessary to convert the motor circuit into an inverter to perform variable speed control, which is very expensive. Further, in a small crane or an old crane, there is no space for remodeling a panel to be an inverter, and due to a problem in the strength of the panel associated with the remodeling, a predetermined strength standard may not be satisfied, and automation is not possible.

Therefore, the problem to be solved by the present invention is to provide a method capable of realizing highly accurate steady rest control at low cost and in a small space even in a notch type control device having no inverter control circuit. It is in.

[0006]

In order to solve the above problems, the crane steady rest control method of the present invention is a steady rest in a crane operating method for traversing and traveling a suspended wire crane by switching a notch circuit. In the control method, at the time of start-up, the notch circuit is turned on at a predetermined timing after starting the start-up to prevent steadying,
At the time of stop, the steady rest is carried out by inserting a reverse notch or by mechanical braking.

As a method of inserting the notch circuit at the time of starting, after the notch is once inserted, the notch is again inserted at a timing after 1/2 of the runout cycle to cancel out the runout energy when the first notch is entered, Perform steady rest.

As a method of turning on the reverse notch or mechanically braking at the time of stop, once the notch is turned on or mechanical braking is performed, 1 is set at a timing half the swing period later.
Single or multiple reverse notch turns or mechanical braking,
At the timing of 1/4 of the runout cycle, reverse notch insertion or mechanical braking is performed one or more times to reduce traverse or traveling speed, and after stopping, the remaining distance from the target position is measured again and the crane traverse direction or Adjust the position in the traveling direction.

[0009]

According to the present invention, in the control method of operating the crane by the notch circuit without the variable speed control means such as the inverter, the notch circuit is turned on at the time of start-up so that the crane accelerates to the first speed and becomes a constant speed state. 1 / of the swing cycle
2, that is, the notch is inserted again in a state in which the shake direction and the traveling direction are the same, the second speed is accelerated, and the vehicle runs at a constant speed to suppress the initial shake and operate. When stopped,
The first deceleration is performed by the first reverse notch or the mechanical brake, and the second deceleration is stopped by the second reverse notch or the mechanical brake in the state where the shake direction and the braking direction are the same. As a result, the crane stops while suppressing the runout.

[0010]

EXAMPLES The present invention will be specifically described below with reference to examples. FIG. 1 is a block diagram of a steady rest control system for carrying out the method of the present invention. This is to realize steady rest control by switching a secondary resistor without using a variable speed control device such as an inverter unlike the conventional steady rest control.

In the figure, 1 is a three-phase AC power source, 2 is a power switch, 3 is a motor, 3a is a primary side field winding of the motor 3, 3b is a secondary side rotor winding of the motor, and 4 is a secondary. The resistor group 5 is a contactor group that controls the switching of the notch of the secondary resistor group 4.

FIG. 2 is an explanatory diagram of a traveling control system for carrying out the steady rest control method of the present invention. In the present invention, the relay circuit 10 is added to the existing indirect control system so that the contactor 11 can be operated by turning on the relay.
In the figure, 12 is a manual controller, 13 is a traveling motor, 1
4 is a reduction gear, 15 is a brake, and 16 is a wheel. During braking, braking with the reverse notch puts a load on the motor and gear system.
By pushing at 8, the brake operation is performed.

FIG. 3 is an illustration of the traverse control system. The traverse controller 20 of the existing direct control system is provided with a controller 21 capable of operating the operation handle, and control is performed by rotating the operation handle with a servo motor based on a command from the control panel 22. Since there is no brake on the traverse, the reverse notch is used for braking, similar to manual operation. In the figure, 23 is a traverse motor, 24 is a reduction gear, and 25 is a wheel.

FIG. 4 is an explanatory view of the winding control system, in which a relay circuit 30 is added to the existing indirect control system so that the contactor 31 can be operated by the relay. In the figure, 32 is a manual controller, 33 is a winding motor, 34 is a reduction gear, 35 is an electromagnetic brake, 36 is a wire drum, and 37.
Is a wire and 38 is a thruster brake. Since the winding control system has a heavy load of several tens of tons, the braking force is strong and it does not start with 1 to 2 notches. Therefore, the notch insertion method is special, such as once inserting into 3 notches and then inserting into 1 notch.

FIG. 5 shows a C hook 39 attached to the tip of the wire 37 of the crane. The C hook 39 and the wire 37 are attached via a link 40, and a spring 41 for detecting the presence of a load. Is provided.
FIG. 5A shows the case where there is no coil as a load, and FIG.
When the coil 42 is suspended from the C hook 39 as shown in FIG. 5, the presence of the load is detected by recognizing the change in the position of the center of gravity due to the change in the spring 41 as a shake.

The control method of the present invention in the crane device having the above-mentioned structure will be described below.

1) Traverse steady rest control FIG. 6 shows an outline of the transverse steady rest control operation. First, from the start of acceleration to the constant speed, insert a notch according to the runout. At this time, the notch is always inserted at the timing to suppress the shake. If you insert the notch so that it accelerates in the opposite direction to the shake direction, the shake will expand, so be sure to insert the notch so that it accelerates in the same direction as the shake direction.

In the deceleration method, the reverse notches are applied so that the energies shaken by the braking at the first-stage reverse notches cancel each other out at the second-stage reverse notches. As for the closing timing, in addition to swing feedback, closing by feedback is 1/2 of the swing cycle, so it is effective as a steady rest even if a two-stage reverse notch is inserted from the latter half on the timing of the time axis. .

In the transverse shake control, it is impossible to achieve both the steady stop and the positioning because the control range by the notch control is limited, so that the control in mm unit is not possible. Therefore, the control for the steady rest and the control for the positioning center are separated and used properly. FIG. 7 shows a speed pattern of each operation (long operation, short operation, fine movement operation).

FIG. 13 is a flow chart showing steps of the steady rest method by the notch control of the present invention.

First, from the stopped state in step 100, the notch is inserted in step 110 to perform one-step acceleration. Next, in step 120, after ½ of the shake cycle, the notch is inserted again to perform two-step acceleration. As a result, constant speed operation is performed as shown in step 130. When the target position is approached, in step 140, reverse notch insertion or mechanical deceleration is performed to decelerate. Then, in step 150, after ½ or ¼ of the shake cycle, reverse notch insertion or mechanical deceleration is performed again. If the crane is stopped in step 160, the remaining distance from the target position is measured by the rotation speed detector (encoder) attached to the drive wheel in step 170, and if the remaining distance is within the allowable range (step 180), Operation complete (step 19)
0). If not, the position is adjusted by the fine movement operation (step 200) and the process returns to step 170.

2) Travel control When the inertial force of the suspended load is large, such as when the coil is loaded, the braking force is increased to prevent steadying. At the time of braking, the timing of applying the brake is set to 1/2 of the swing cycle to perform the braking.
The load is shaken to the braking side by the first-stage brake, and braking is performed so that the energies shaken by the second-third brake cancel each other out. FIG. 8 shows the control flow.

During braking when the inertial force of the suspended load is small, such as when there is no coil, the brake closing interval is set to 1 of the swing cycle.
By setting to / 4 and applying the multi-stage brake, the vibration during braking is gradually suppressed and stopped. That is, the multi-stage brakes reduce the speed and the vibration by braking in the direction in which the loads shaken by the braking are canceled out. As a result, the steady rest can be easily achieved and the allowable range is large. FIG. 9 shows the control flow. When the inertia is large, the braking force by the multi-stage brake does not act against the vibration, so this braking method is applied only when the load is light.

FIG. 10 shows a steadying and positioning pattern. In the case of braking by the brake, the closing timing and the braking force depending on the deflection direction of the first-stage brake are unstable, and thus the positional deviation occurs, so that both the steady stop and the positioning are not performed, and the pattern shown in FIG. , Each mode of steady rest priority and positioning priority is prepared and used by switching. In addition, also in traveling control,
A flow chart showing the steps of the steady rest method is represented in FIG.

3) Winding control Winding control In the winding operation, when the hook is sufficiently inserted due to the characteristics of the C hook, the load cannot be physically dropped. Therefore, after the load is temporarily stopped, the load is stopped. , Winding up to the target. This pattern is shown in FIG.

Unwinding control Since soft landing is carried out during unwinding, stoppage is carried out by detecting loading. Since this load detection can be recognized as a change in the position of the center of gravity of the C hook, that is, a swing of the wire rope,
This can be done by a deflection angle detector. This pattern is shown in FIG.

[0027]

As described above, according to the present invention, highly accurate steady rest control can be realized at low cost and in a small space even in a notch type control device having no inverter control circuit.

[Brief description of drawings]

FIG. 1 is a block diagram of a steady rest control system for carrying out the method of the present invention.

FIG. 2 is an explanatory diagram of a traveling control system for implementing the steady rest control method of the present invention.

FIG. 3 is an explanatory diagram of a traverse control system.

FIG. 4 is an explanatory diagram of a winding control system.

[Fig. 5] C attached to the wire end of the crane
It is explanatory drawing which shows a hook.

FIG. 6 is an explanatory diagram showing an outline of the lateral steady rest control.

FIG. 7 is a diagram showing a speed pattern of each operation in the present invention.

FIG. 8 is an explanatory diagram showing a flow of travel control when a heavy load is applied.

FIG. 9 is an explanatory diagram showing a flow of travel control when a light load is applied.

FIG. 10 is an explanatory diagram showing patterns of steady rest and positioning.

FIG. 11 is an explanatory diagram showing a winding control pattern.

FIG. 12 is an explanatory diagram showing a pattern of unwinding control.

FIG. 13 is a flowchart showing steps of a steady rest method by notch control according to the present invention.

[Explanation of symbols]

1 3 phase AC power supply, 2 power switch, 3 motor, 3
a primary side field winding, 3b secondary side rotor winding, 4 secondary resistor group, 5 contactor, 10 relay circuit, 11 contactor, 12 manual controller, 13 traveling motor,
14 reduction gears, 15 brakes, 16 wheels, 17
Foot brake, 18 air cylinders, 20 traverse controller, 21 controller, 22 control panel, 23
Traverse motor, 24 reduction gear, 25 wheels, 30 relay circuit, 31 contactor, 32 manual controller, 3
3 winding motor, 34 reduction gear, 35 electromagnetic brake, 36 wire drum, 37 wire, 38 thruster brake, 39 C hook, 40 link, 4
1 spring, 42 coils

Claims (3)

[Claims] 1. A steady rest control method in a crane operation method for traversing and traveling a suspended wire crane by switching a notch circuit, wherein the notch circuit is turned on at a predetermined timing after the start of the start. A crane steady rest control method characterized by carrying out steady rests and inserting a reverse notch or stopping by mechanical braking when stopping. 2. As a method of inserting a notch circuit at the time of starting,
2. The notch is once inserted, and then the notch is again inserted at a timing after 1/2 of the runout cycle to cancel the runout energy at the time of the first notch insertion to perform the steady rest. Crane steady rest control method. 3. As a method of applying a reverse notch or mechanical braking at the time of stop, once the notch is inserted or mechanical braking is performed, and then once or a plurality of times at a timing ½ of the runout period. Reverse notch insertion or mechanical braking is performed, or reverse notch insertion or mechanical braking is performed once or multiple times at a timing after 1/4 of the runout period to reduce traverse or traveling speed, and after stopping, the target position is set again. The crane steady rest control method according to claim 1 or 2, wherein the position in the traverse direction or the traveling direction of the crane is adjusted by measuring the remaining distance of the crane.