SU1730021A1 - Bucket crane winch control device - Google Patents

Abstract

This invention relates to lifting devices. The device contains two reverse thyristor converters 1 and 12, each connected to electric motors 2 and 13 with tachogenerators 3 and 14 and sensors 9 and 20 of the current of the main supporting and closing winch, and for each of them an electric drive control system with serially connected command devices 4 (15), adder 5 (16) speed command signals and tachogenerators 3

Description

The invention relates to lifting devices, namely to electric winch control devices,

The purpose of the invention is to increase the reliability of the winches.

FIG. 1 is an electrical diagram of a device for controlling a winch of a clamshell crane; 2 is an electrical diagram of the mode of operation.

electric drive of the grapple winches; on fig.Z - logic board; figure 4 - mechanical characteristics of the electric motors supporting and closing the winch when scooping; figure 5 - mechanical characteristics of electric motors supporting and closing winches when lifting a filled grab; figure 6 - the mechanical characteristics of the electric motors supporting and closing the winches during the descent of the empty grab; 7 - the truth table of the logic board,

A winch control device for a grab crane consists of a reversible thyristor converter 1 for supplying a support winch motor 2 with a tachogenerator 3 and a support winch electric drive control system, in series with the speed controller and tachogenerator 3, regulator 6 speeds of the motor 2, the board 7 limits the output signal of the speed controller 6, the adder 8 signals for the current cor and the sensor 9 for the current cor winch, regulator current 10 core and system 11 of the phase-pulse control. The reverse thyristor converter 12 for powering the trailing winch motor 13 with a tachogenerator 14 contains a trailing winch electric drive control system that has a control unit 15 in series, an adder 16 for speed reference and a tachogenerator 14, a speed regulator 16, a fee 18 for limiting the output signal of the regulator 17 speed, the adder 19 of the current command signal and the core current sensor 20, the core current regulator 21 and the phase-impulse control system 22. As a connecting link between the support and closing winches control system, the switch 23 for setting the winches electric drive control function, the mode set plate 24, the grab closing sensor 25, the logic board 26, 27 are installed. The first outputs of the boards 26, 27 are connected to the first inputs of the third and fourth electronic keys 28.29. The second and third inputs of the third and fourth electronic switches 28, 29 are interconnected respectively and connected to two sources 30 and 31 of the reference voltage. Each of the outputs of the third and fourth electronic switches 28 and 29 is connected directly and through inverters 32 and 33 to the boards 7 and 18 of the limiting output signals of the speed controllers 6 and 17 supporting and closing winches. The second output of the logic board 26 is connected to the input of the first electronic key 34, and the second output of the logic board 27 is connected to the input of the second electronic key 35. The output of the first electronic key 34 is connected to the speed controller 6 of the supporting winch, and the output of the second electronic key 35 is connected to the regulator torus 17 speed closing winch.

The electrical diagram of the operating mode of the electric drive of the grapple winches (FIG. 2) contains a command winder 4 of the supporting winch, which has

microswitches 36 for lifting and 37 lowering, and a self-locking winder control unit 15 with microswitches 38 for lifting and 39 lowering, and also a mode dial 24, which contains a relay set. Two relays 40, 41 with

coils, the current circuit of which is closed at the neutral position of the control knob 4 and 15, the corresponding contacts 42, 43. Two relays 44 and 45 with coils, the current circuit of which closes

when the control knob is set to the Lift position, and the corresponding contacts 46, 47. Two relays 48, 49 with coils, the current circuit of which closes when the Commander's control knob is set to the Trigger position and the corresponding contacts 50, 51, and also output relay 52 with a coil and contacts 53, 54.

The winch control device of the grapple crane operates as follows.

We consider the work of the grab from the moment when the opened grab lies on the scooping material. Both control units 4 and 15, supporting

and the closing winches are in a neutral position. In accordance with the scheme of FIG. 2, the boards 24 of the set of modes of the relay 40, 41 are underflow, the relay 52 is de-energized, and the output of the board is

unit.

By logical unit is meant a high level of voltage or an open circuit, by logical zero is meant a low level of voltage.

The winch drive control function setting switch 23 is set to the position shown in FIG. 1. This means that the electric motor 2 controls the supporting winch and the electric motor 13 controls the closing winch. Logical zero arrives at logic logic board 26 of the supporting winch, and logic logic unit one arrives at logic logic board 27 of the closing winch.

Before starting the winches for both

The electric motor is set to the required magnitude of the current limitation, equal to 1.5 1H, where 1H is the rated current of the electric motor. This is accomplished by setting the magnitude of the signal of the voltage source 30, which passes through the third and fourth electronic switches 28 and 29 directly and the inverters 32 and 33 and goes to the inputs of the boards 7 and 18 of the output limit of the regulators 6 and

17 of the speed of the supporting and closing winches, and, thereby, the necessary limiting value of the current of the core is set, is equal to the starting one. Inverters 32 and 33 with a gain equal to one are necessary to ensure that the output signals of the speed controllers 6 and 17 are limited to plus-minus.

Logic boards 26 and 27 are inputted into the automatic winch control system to interconnect the closing and supporting the winch with a two-cable grab and, according to the instructions for setting the technological mode of operation of the winch, generate commands for the formation of the mechanical characteristics of the supporting and closing winch motors. The logic board 26 (27) contains the combinational circuit shown in FIG. The input of the logic board receives three signals. X1 is the task signal coming from the recruitment board 24, while X1-0 (logical zero) corresponds to operation with an open grab, X1 1 (logical unit) to operation with a closed grab. Working with a closed grab means scooping up, lifting a closed grab, and working with an open grab means opening the grapple, lowering the open grab, lifting the open grab.

X2 - the signal from the sensor 25 to close the grab, while X2 0 corresponds to the condition: the jaws of the grab are closed. X2 1 - the jaws of the grapple are opened. X3 is the signal from the switch 23 for setting the winch drive control function, whereby XZ 0 corresponds to the drive control of the electric motor 2 of the supporting winch, KhZ 1 is driving the drive of the electric motor 13 of the closing winch.

At the output of each of the logic boards 26, 27 there are two outputs, while the output 1 of the logic board 26 is connected to the third electronic key 28, and the output 2 is the first key 34. The output 1 of the logic board 27 is connected to the fourth electronic key 29, and output 2 -e second electronic key 35.

The control commands of the four electronic keys 28, 29, 34, and 35 are formed as follows.

The material is picked up with a grab when the command and control unit 15 of the closing winch is moved to the Rise position. With a time delay in the Rise position, the command device 4 supporting the winches is transferred. At the input of the board 27 of the logic of the closing winch there will be signals: X1 1, X2 1, X3 1, on

output 1-1, output 2-1 (see Fig. 7 - table of truth of the logic board). Under such conditions, the electric motor of the closing winch operates on a hard characteristic with current limiting core at 1 1.51N.

At the input of the board 26, the logic of the supporting winch will be signals: X1 1, X2 1, X3 0, output 1 0, output 2-1.

0 Output 1 of board 26 of the logic of the supporting winch receives a signal (logical zero) to the third electronic switch 23, which switches over by disconnecting the source 30 of the reference voltage and

15 is connected to the reference voltage source 31, thereby changing the current reference limit of the support winch core at 10% of the rated motor current. Consequently, the electric motor 8 of the supporting winch operates with a current limiting of a core of 10% of 1H, and the electric motor 13 of the closing winch operates on a rigid characteristic with a current limiting of a core of 1.51N. Restriction of the current of the supporting winch core occurs after the command device 4 is set to the Rise position. The type of mechanical characteristics of both winches when scooping is shown in figure 4.

0

When a grab closure signal is received (logical zero) from the sensor 25, the grapple is closed at the input of the board 26 of the logic of the supporting winch. Signals: X1 1, at the output 2 0, the output (1) of the third electronic key 28 and switches, connecting the voltage source 30, thereby changing the current limit of the electric motor of the supporting winch, and the initial limit is set at level 1. Simultaneously with switching the limitation of the electric motor core of the supporting winch from the output 2 of the logic board 26, a logical zero signal is sent to the first electronic key 34, which before this moment of time was in the open state, which causes the key to close. This leads to the shunting of a part of the resistors included in the feedback circuits of the speed controller 6 and a change (decrease) in the gain of the controller 6 in the speed of the supporting winch.

At the output of the logic winch logic board 27 after the end of the scooping mode, there will be signals: X1 1, X2 O, X3 1, at the output 1 1, at the output 2 1. Since the outputs of the logic board 27 are before scrapping and

After the grab has been closed, it has not changed, and the mode of operation of the closing winch has not changed.

When both winches are on the rise, the mechanical characteristics of the supporting winch electric motor have a greater slope than the mechanical characteristics of the closing winch, since the gain of the speed regulator of the supporting winch is less than that of the closing winch. The stiffness of the characteristics is chosen from the condition that when lifting a full grab, the moment in the supporting winch is 40%, and the closing one is 60% of the time needed to raise the full grab. This distribution of the moment ensures reliable closing of the grapple during lifting. The mechanical characteristics of the electric motors of both winches when lifting a full grab are shown in Fig.5.

When the grapple is raised to a predetermined height, both control units are set to the neutral position. To open the grapple in an elevated state, it is necessary to transfer the locking winch command device 15 to Descent when the tempered device 4 of the supporting winch is in a neutral position or to move the command unit 4 to the locking winch position of the operating device 15. In this case, the mode dialing circuit generates the X1 0 signal at the output. Signals are input to the logic board 26: X1 O, X2 O, X3 0. At the output 1 1, at the output 2 1. At the second output, Oth.2 of the board 26 instead of logical zero a logical unit appeared. This causes the first electronic switch 34 to open and connect part of the resistors in the feedback circuit of speed controller 6, thereby increasing the gain of the controller.

Signals enter the input of logic board 27: X1 O, X2 O, X. 1. At the first output of logic board 27 Ex.1, a logical zero appears on the fourth electronic switch 29, which switches the source 30 of the reference voltage to the source 31 the reference voltage and, thus, on the closing winch, the core current is limited to 10% of the rated current.

When the grab is fully deployed from the grapple closure sensor 25, a disclosure signal is received. The following signals appeared at the input of the logic board 26: X1 O, X2 1, X3 0, output 1 1, output 2 1. The operating mode of the supporting winch did not change. The following signals appeared at the input of the logic board 26: X1 0, X2 1, X3 0, output 1 0, output 2 1, the mode of operation of the closing winch did not change.

For lowering the opened grapple, the controller 15 of the closing winch is set to the Descent position. With a time delay, the descent of the control unit 4 of the supporting winch is set to, and the dialing circuit produces a signal X1 0. Signals are present at the input of logic board 26: X1 O, X2 1, X3 0, output 1 1, output 2 1. Mode The work of the supporting winch has not changed. At the input of logic board 27, the input signals are: X1 O, X2 1, X3 1, output 1 0, output 2 1. The operating mode of the supporting winch has not changed. The descent takes place with a rigid mechanical characteristic of the engine supporting the winch and with the limitation of the current of the core at the level of 0.11 n of the electric motor of the closing winch.

Claims (1)

Claims An apparatus for controlling a winch of a grab crane, comprising control systems for supporting and closing winch motors, each of which is equipped with a reversible thyristor converter connected to the corresponding winch electric motor, tach generator, core current sensor, and sequentially connected rotary device, summator speed command signal and tacho generator signal, speed controller with output limit card, sum The signal of the board for setting the current of the core and the signal of the current sensor of the core, the current regulator of the core and the system of phase-pulse control, while the device is equipped with a sensor for closing the grapple, which is designed to increase the reliability of the winches a set of modes, two logic boards, a switch for setting the winch motor control function, two reference voltage sources and four electronic keys, each three inputs of the mode set board are connected to the corresponding control panel, the output of this board is connected to one of the inputs of each logic board, the second inputs of the logic board are connected to a switch for setting the control function of the winch motors, the first outputs of each logic board are connected to the first inputs of the third and fourth electronic switches, the second outputs of each of the logic boards logic connected to the inputs of the first and second electronic keys, while the second and third inputs of the third and fourth electronic keys are connected respectively to each other and connected to two sources of reference voltage, the output of the third key is connected directly and via an inverter to the output limit control card of the speed regulator supporting winch, and the fourth key output is connected directly and via an inverter to the output limit card of the output speed controller of the closing winch, and two outputs of each of the electronic keys are connected respectively to the speed controllers of the supporting and closing winch. Mr. O 01 g 5bix.f C -about ABOUT) 1h -about .Support winch About 0.1 8 out 2 | figm 1J5 W § one% Ј§ Sf 1 with Q s: 0 I 0i / 8.7