SU1539815A1 - Emergency alarm device - Google Patents

Abstract

This invention relates to automated process control systems and can be used in emergency protection and alarm systems in the metallurgical, chemical, energy, and other industries. The aim of the invention is to increase the functional reliability of the device. The purpose of the invention is achieved in that a device comprising a pulse generator 1, an AND 2 element, a pulse counter 3, sensors 4, a multiplexer 5, a decoder 6, indicators 7, a delay element 10, a trigger 11, an alarm output 12, a reset button 13, polling button 14, triggers 15, controllable keys 16 and 17, common bus 18, element 8 and element NOT-9 are entered. Sensor 4 outputs through multiplexer 5 are alternately connected to input of decoder 6 and to element input AND-HE 9. In the absence of an accident, the operation of the decoder 6 is prohibited. In the event of an accident, trigger 11 switches, generates an alarm signal and stops the pulse counter 3, information from which through the decoder 6 enters the indicators 7, thereby fixing the first triggered sensor 4. The remaining sensors 4 are triggered by triggers 15. address signals at the input of the multiplexer 5, does not cause false switching of the triggers 15, because the duration of the interference at the input of the triggers 15 is less than the pulse duration at the input of the decoder

Description

5, decoder 6, indicators 7, delay element 10, trigger 11, alarm output 1, reset button 13, interrogation button 1, triggers 15, control keys 16 and 17. common bus 18, HE element 8 and I element are entered NOT 9. The sensor outputs k through the multiplexer 5 are alternately connected to the input of the decoder 6 and to the input of the element AND-HE 9. In the absence of an accident, the operation of the decoder 6 is prohibited. In the event of an accident, trigger 11 is switched, generating an alarm signal and stopping the pulse counter 3, information from which through the decoder 6 enters the indicators 7 thereby

I fixed the first sensor that worked. The operation of the remaining sensors 4 is remembered by the triggers 15. Availability

interference that occurs when address signals change at the input of multiplexer 5 does not cause false switching of triggers 15, since the duration of the interference at trigger input 15 is less than the pulse duration at the input of the decoder 6, and trigger 11 switches with a delay longer than the interference, therefore hera 15 records only

true alarms from the outputs of sensors 4, 1 Il.

This invention relates to automated process control systems and can be used in emergency protection and alarm systems in the metallurgical, chemical, energy, and other industries.

The aim of the invention is to increase the functional reliability of the device.

The drawing shows a block diagram of an alarm device.

The device contains a pulse generator 1, element 2, pulse counter 3, sensors kt multiplexer 5, decoder 6, indicators 7, elements HE 8, AND-HE 9, delay element 10,

trigger 11, alarm output 12, reset button 13, And poll button, triggers 15, control keys 16 and 17, and common bus 18.

The device works as follows.

In the initial state by pressing. the reset button 13, the trigger 11 is set to state 1, and the pulse counter 3 is set to state O. From the output of trigger 11, signal 1 is fed to the first input of the element I 2, as a result of which the pulses from the output of the generator 1 of the pulses go through the element 2 to the counting the input of the counter 3 pulses and the input of the element 10 delay.

The signals from the output of the counter 3 pulses are fed to the address inputs of the multiplexer 5 and information

Q

five

0

five

0

inputs of the decoder 6, and from the output of the delay element 10 - to the gate input of the decoder 6. The sensor outputs through multiplexer 5 are alternately connected to the gate input of the decoder 6 and to the input of the NAND element 9. In the absence of an alarm, the signal on the inverse output of the multiplexer 5 corresponds to the signal O , the operation of the decoder 6 is prohibited, and the signal 1 is saved at the output of the NAND 9 element. The triggers 15 connected to the sensor outputs kt are in state 1. When the decoder 6 is disabled, the signal 1 is also set at its outputs The controlled keys 16 are connected to the open contact of the polling button 1, and the controlled keys 17 are connected to the outputs of the flip-flops 15. Since the control inputs of the controlled keys 16 and 17 are set to signals 1, they are closed.

In the event of an accident, any of the sensors triggers and at the time of its polling the signal at the output of multiplexer 5 changes its logical value, which leads to switching of the trigger 11 to the state O and, therefore, blocking the element AND 2. The set of elements is HE 8, N-9 provides blocking of the trigger 11 for the duration of the signal 1 at the output of the pulse generator 1, when it is possible to generate false information.

At the output of the trigger 11 An output signal is generated for emergency shutdown of the control system to ensure 515

pi of her protection. In this case, the pulses are not received at the counting input of the counter 3; the process of polling the sensors k is stopped. The gating inputs of the decoder 6 enable signals from the output of multiplexer 5 and through the delay element 10 from the output of element 2. The information supplied to the inputs of the decoder 6 and the corresponding address of the triggered sensor 4 is fed through the decoder 6 to the input of the indicator 7 corresponding to the number of the triggered sensor . Thus, the first crash is detected.

When alarms accompanying the first occur (the triggering of subsequent sensors) occur, they are memorized by the corresponding triggers 15, at the outputs of which they set

The signals O are turned on, which include the corresponding controlled keys 17. When the And poll button is turned on, the O inputs of the controlled keys 16 receive a signal O and through the controlled keys 16 and the controlled keys 17 determined by the zero state of the trigger 15, the corresponding indicators 7 are connected to common bus. Their luminescence determines the numbers of the alarms that accompany the first one and, therefore, the numbers of the activated sensors. ,

After the accident has been eliminated, returning the circuit to the initial state is performed by turning on the reset button 13.

In devices with branched information links between nodes, there can be crosstalk between inputs during the change of address signals. In a device, a branched node is a multiplexer 5 and, therefore, during the time when the address signals change at its input, interference occurs at its information inputs.

However, the presence of interference at the information input of multiplexer 5 does not cause false switching of the triggers 15. Since the duration of the interference at the inputs of the flip-flops 15 is much shorter than the pulse at the input of the decoder 6 and, respectively, at the input address of the multiplexer 5, and the trigger 11 switches with a delay that is more interference then by the moment of switching the trigger 11 to zero sos,

ten

15

20

25

thirty

35

40

45

50

55

15

The fact that its inverse signal of a logical unit permits writing only only true emergency CHI - signals from the sensor outputs 4 into the trigger 15.

Claims (1)

Invention Formula An alarm device comprising a pulse generator, the output of which is connected to the first input of the element I, the output of which is connected to the counting input of the pulse counter and to the input of the delay element whose output is connected to the first gate input of the decoder, the outputs of which are connected to the corresponding indicators and informational the inputs of the corresponding controlled keys of the first group, the outputs of which are connected to the information inputs of the corresponding controlled keys of the second group, the outputs of which are They are shared with the common bus, the pulse counter outputs are connected to the information inputs of the decoder and to the address inputs of the multiplexer, the output of which is connected to the second gate input of the decoder, sensors whose outputs are connected to the corresponding information inputs of the multiplexer and the first inputs of the corresponding trigger group, the outputs of which are connected to the control inputs of the corresponding controlled keys of the second group, a reset button, which is connected to the input of the installation in the pulse counter and the first input the meter, the first output of which is the output of the device and connected to the second input of the element I, the reset button which is connected to the control inputs of the controlled keys of the first group, the second inputs of the group triggers, which in order to increase the functional reliability of the device, The element НЈ and the element NAND are entered into it, the output of the pulse generator through the element is NOT connected to the first input of the element IS-NOT whose output is connected to the second input of the trigger, the second input of which is connected to the second input of group triggers, the multiplexer output is connected to the second input of the NAND element.