SU1474039A1 - Device for locking conveyer drive - Google Patents

Abstract

The invention relates to mining electrical engineering and is intended for remote shutdown of conveyors, the working body of which in emergency situations is shifted away from the established direction. The goal is to increase the reliability of the device. It contains an alternating current source 1, a selector 2 polar signals, the first 18 and second 19 wires of a communication line with a series-connected cable - cable switches 20, a tape sensor 21, an end diode 23, an output unit 17, a pulse shaper 8, high-frequency a transformer 7, a logic block 9, a sensor 22 for monitoring the state of the fence on the landing pads and diodes 24.25. The logic block 9 contains converters 10-12, a decoder 13, an indicator 16, a delay line 14, and an OR 15 unit. The device conducts four commands to disconnect the conveyor drive with indication of the cause of the shutdown and a normal signal by wires 18,19. operation. At the same time, a time delay for switching off and blocking the drive is performed when the tape derailment sensor 21 triggers. This eliminates false disconnections of the conveyor and the use of an apparatus that excludes false disconnections of the conveyor due to the short-term descent of the conveyor belt to the side. In the communication line, m. The contacts of other sensors or devices are included. 1 hp ff, 2 ill.

Description

one

four

ABOUT

with

WITH

Transformer 7, logic block 9, sensor 22 for monitoring the condition of the fence on the landing sites and diodes 24, 25. Logic block 9 contains converters 10-12, decoder 13, indicator 16, delay line 14 and element OR 15. Device via wires 18, 19, the communication line transmits four commands to disconnect the conveyor drive with an indication of the reason for the disconnection and a signal of normal operation.

In this case, a time delay is performed for switching off and blocking the drive when the belt off sensor 21 triggers. This eliminates false disconnections of the conveyor and the use of an apparatus that excludes false disconnections of the conveyor due to the short-term descent of the conveyor belt to the side. In the communication line m. B. The contacts of other sensors or devices are included. 1 hp ff, 2 ill.

one

The invention relates to mining electrical engineering, mainly to intrinsically safe devices for remote shutdown of conveyors (or other flow-transfer mechanisms), whose working body in emergency situations is shifted away from the established direction, while the communication line of the drive shutdown must have a protective failure, i.e., in the event of a break or short circuit, the drive of the flow-transfer mechanism must be switched off.

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

FIG. 1 shows a block diagram of the proposed device; in fig. 2 is a signal state table.

The device contains an alternating current source 1, a selector 2 polar signals, including a diode 3, a resistor 4 and optocouplers 5 and 6, a high-frequency transformer 7, a pulse shaper 8, a logic block 9 containing converters 10-12, a decoder 13, a delay line 14, the element OR 15 and the indicator 16, the output unit 17, the first wire 18 of the communication line, the second wire 19 of the communication line, cable-wire switches 20, tape runoff sensors 21, sensors 22 for monitoring the state of the fence on the landing sites, end diode 23 and diodes 24 and 25.

The device works as follows.

In the initial state, the contacts of the switches 20 are closed, the contacts of the sensors 21 and 22 are open.

A positive polarity current flows through the optocoupler 5, the primary winding of the high-frequency transformer 7, the first wire 18 of the communication line, the closed contacts of the switches 20, the end diode 23, the driver 8 of the pulses and the second wire 19 of the communication line.

Since the current of positive polarity flows through the shaper of 8 pulses, its pulses have a steep front. As a consequence, with the secondary winding of the high-frequency transformer 7 on the three

five

0

five

0

five

0

This input of logic block 9 receives a signal. At the same time, the optocoupler 5 generates a signal at the first input of the logic block 9.

A current of negative polarity flows through the optocoupler 6, resistor 4 and diode 3. As a result, optocoupler 6 outputs a signal to the second input of logic block 9.

Thus, in the initial state, corresponding to the normal mode of operation of the conveyor and the healthy state (no break and short circuit) of the communication line, all three inputs of the logic block 9 will have signals (Fig. 2, line 1).

When one of the sensors 21 controlling the descent of the tape triggers, the current of positive polarity flows similarly to the initial state. As a result, signals are output to the first and third inputs of the logic block 9. A negative polarity current flows through the second wire 19 of the communication line, the closed contact of the first sensor 21, the diode 24, the first wire 18 of the communication line, the primary winding of the high-frequency transformer 7 and the diode 3.

At the same time, a negative polarity current flows through the optocoupler 6, resistor 4 and diode 3.

When the ohmic resistance of the resistor 4 is greater than the ohmic resistance of the primary winding of the high-frequency transformer 7, the current passing through the optocoupler 6 is significantly reduced, and at the output of this optocoupler and at the second input of logic block 9 the signal disappears (Fig. 2, line 2).

When one of the emergency shutdown switches 20 is triggered, the current of positive polarity does not flow, as a result of which the signals at the first and third inputs of the logic block 9 disappear. The current of negative polarity flows through the optocoupler 6, resistor 4 and diode 3, as a result of which a signal arrives at the second input of logic unit 9 (Fig. 2, line 3).

In case of short circuit of the communication line, the current of positive polarity flows through

optocoupler 5, the primary winding of the high-frequency transformer 7, the first wire 18 of the communication line and the second wire 19 of the communication line. Since in this case a current flows through the primary winding of the high-frequency transformer 7, the pulses of which have a sinusoidal shape, the signal disappears at its output and the third input of logic block 9, and the signal goes to the first input of logic block 9 from the optocoupler 5.

The negative polarity flows through the first 18 and second 19 wires of the communication line, the primary winding of the high-frequency transformer 7 and diode 3. As a result, the current of negative polarity simultaneously flowing through the optocoupler b, resistor 4 and diode 3 is significantly reduced, and the signal to the output of the optocoupler 6 and the second input of the logic block 9 disappears (Fig. 2, line 4).

When a fencing sensor 22 is triggered, the positive polarity flows through the optron 5, the primary winding of the high-frequency transformer 7, the first wire 18 of the communication line, the diode 25, the closed contact of the sensor 22 and the second wire 19 of the communication line. Since in this case a current flows through the primary winding of the high-frequency transformer, the pulses of which are sinusoidal, the signal disappears at its output and the third input of logic block 9, and the signal arrives at the first input of logic block 9 from the optocoupler 5. The current of negative polarity flows through the optocoupler 6, resistor 4 and diode 3, as a result of which a signal arrives from this optocoupler to the second input of logic block 9 (Fig. 2, line 5).

The device can operate while executing the communication line with both cable and bare wires (two-wire air line), while the two-wire communication line transmits four commands to disconnect the conveyor drive with indication of the reason for the disconnection and the normal operation signal time delay for shutting down and locking the drive when a tape derailment sensor is triggered (which eliminates either false shutdowns of the conveyor or the need to use the AKC device that eliminates false shutdowns of the conveyor due to the short-term runoff of the conveyor belt to the side), to the two-wire line

Communications may include the contacts of other sensors or devices.

Claims (2)

1. A locking device for a conveyor drive, containing an AC source, connected to a polar signal selector, a two-wire communication line with series-connected cable-wire switches and parallel-connected tape derailment sensors and an end diode, an output unit characterized in that in order to increase reliability, a pulse former, a high-frequency transformer, with a logic unit, a sensor monitoring the state of the fence on the landing pads and diodes, while this pulse shaper is connected between the cathode of the end diode and the second wire of the two-wire communication line, and the sensor monitoring the state of the fence on the landing pads is parallel to the tape derailment sensors between the first and the second wire of the two-wire communication line, while between the first wire of the two-wire communication line and the sensor for monitoring the state of the fence on the landing sites a diode is connected similarly to the end one, and between the sensors The tapes and the first wire of the two-wire communication line are connected to the opposite end of the polarity diodes; the primary winding of the high-frequency transformer is connected between the first output of the polarity selector and the first wire of the two-wire communication link; the second and third outputs of the pulse selector are connected respectively to the first and second logic block inputs 5 to the third input of which the secondary winding of the high-frequency transformer is connected, the output of the logic unit is connected to the input of the output unit. 2. The device according to claim 1, characterized in that the logic block contains three converters, a decoder, an indicator, a delay line and an OR element, and the outputs of the converters are connected to the inputs of the decoder, the first output of which is connected to the corresponding indicator input and through the delay line element input - OR, the remaining outputs of the decoder are connected to the corresponding inputs of the indicator and the OR element, while the inputs of the converters are the inputs of the logic block, and the output of the OR element is its output. FIG. 2