CN2526842Y

CN2526842Y - Combustible gas leakage detector

Info

Publication number: CN2526842Y
Application number: CN 02219151
Authority: CN
Inventors: 袁金杨
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-03-04
Filing date: 2002-03-04
Publication date: 2002-12-18
Anticipated expiration: 2012-03-04

Abstract

The utility model relates to a fuel gas leak detector and is characterized in that a signal collection circuit comprises a signal collection amplifier circuit which can do detection to fuel leakage concentration by level, a sensor open-circuit signal collection unit circuit and a signal collection unit circuit which can detect whether the sensor is invalid and short-circuited; a signal analysis and control circuit is formed by a single chip machine; and the utility model also comprises more than two alarm signal output circuits. The device can do multiple multi-level detections and alarms during the leakage according to time segments and also detect whether the sensor is invalid; through intelligent management of the SCMs, the utility model reduces fuel gas leakage pseudomorph or wrong alarm caused by light leakage.

Description

The combustible gas leakage detector

Technical field

The utility model relates to a kind of combustible gas leakage detector.

Background technology

At present, the circuit structure that the combustible gas leakage detector is adopted is commonly operational amplifier, voltage comparator, 555 time base circuits and other digital circuit both as the main components and parts of signal gathering unit, the main components and parts that are also used as control odd-numbered day unit again simultaneously, detector can only carry out disposable detection and simple logic determines to the leak condition of inflammable gas.The weak point of its existence is: one, can not carry out intellectual analysis to the signal of being gathered; Though two, some detector has secondary detection gas leakage function, can not continue to monitor and analyze the combustible gas leakage process, export different alerting signals respectively; Three, detector allows the combustion gas gas sample gathered single; Four, do not have the function that monitoring sensor lost efficacy; Five, do not have extendible networking strange land warning function; Six, can not screen the signal that collects, antijamming capability is not strong, the rate of false alarm height.

Summary of the invention

By improvements over the prior art, the combustible gas leakage detector that the utility model provides a kind of carries out intellectual analysis, have multiple detection, alerting signal is various, false alarm rate is low.

Concrete technical solution is such:

The combustible gas leakage detector, its circuit structure comprises power circuit and signal acquisition circuit, it is characterized in that:

A, described signal acquisition circuit comprise combustible gas leakage concentration are carried out the signals collecting amplifier circuit, open sensor signal gathering unit circuit of hierarchical detection and to the signal gathering unit circuit of whether short circuit failure detection of sensor itself;

The output terminal of B, signal acquisition circuit is connecting the input end that the signal of being made up of single-chip microcomputer divides folding, control circuit;

The output terminal of C, single-chip microcomputer is connecting the alerting signal output circuit more than two.

The amplifier circuit that the described signals collecting amplifier circuit that combustible gas leakage concentration is carried out hierarchical detection is made up of operational amplifier U1A and resistance R 5, R6, R7, capacitor C 3, the positive input two ends of amplifier U1A are connecting R5, C3, its reverse input end is connecting R6, R7, and its output terminal is connecting the single-chip microcomputer input port;

Described open sensor signal gathering unit is made up of operational amplifier U1C and resistance R 2, R11, R12, R13 and sensor internal resistance respectively, and the end of R12, R13 is connected with the positive input of U1C, another termination power of R12, R13 other end ground connection; One end of R11 and sensor internal resistance is connected with the reverse input end of U1C, R11 other end ground connection, and the other end of sensor internal resistance is connected with R2, and the R2 other end is connected with the power supply unit output terminal, and the output terminal of U1C connects the single-chip microcomputer input end;

Described signal gathering unit to whether short circuit failure detection of sensor itself is made up of operational amplifier U1D and resistance R 15, R16, R17, R18 and fuse FUSE1 respectively, the end of R17, R18 is connected with the positive input of U1D, another termination power of R17, the other end ground connection of R18; The end of R15, R16 is connected with the reverse input end of U1D, and the other end of R15 is connected with the power supply unit output terminal, the other end ground connection of R16; The output terminal of U1D connects the single-chip microcomputer input end.

Described alerting signal output unit is respectively more than one luminotron output and hummer output, relay switch output, transistor collector open circuit are exported.

The utlity model has the advantage of following several respects:

One, having adopted with the single-chip microcomputer is the circuit structure at center, merged the advantage separately of traditional circuit and single-chip microcomputer application technology, incident of leakage or leakage illusion at the detected variable concentrations of detector, select corresponding alerting signal or cue output, and in advance these alerting signals or cue have been scheduled to alert levels and warning kind; In time diluted by the exhaust fan of relay switch control or range hood and even gets rid of inflammable gas, the combustible gas leakage that alleviates environment for use pollutes, and reduces the possibility of generation combustible gas leakage explosive incident.

Two, by to the improvement of signal gathering unit circuit, increased voltage comparator, the leakage process of inflammable gas has been carried out at times repeated detection; Combustible gas leakage concentration in the incident of leakage generating process is carried out hierarchical detection; Can also not inefficacy not arranged detecting sensor itself.

Three, can monitor the sensor of two gas samples by increasing collecting unit and sensor number or apolegamy, can make to detect two or more different inflammable gas within the detector.Adapted different size sensor can be monitored, point out and report to the police the leakage of inflammable gass such as the artificial piped gas in city, oil liquefied gas and natural gas as required.

Four, by single-chip microcomputer to detecting and analyze the intelligent management of two links, filtered error signal and undesired signal can reduce the combustible gas leakage illusion, or the false alarm that caused of slight incident of leakage.

Description of drawings

Fig. 1 is the utility model power supply and signal gathering unit circuit electrical schematic diagram,

Fig. 2 is the utility model single-chip microcomputer and warning circuit electrical schematic diagram,

Fig. 3 is the Single Chip Microcomputer (SCM) program block diagram.

Embodiment

By Fig. 1, Fig. 2 as seen, main 4 element circuits of the circuit structure of combustible gas leakage detector, i.e. power circuit, signal acquisition circuit, signal analysis control circuit and the alerting signal output circuit formed by single-chip microcomputer.

A, described signal acquisition circuit comprise to combustible gas leakage concentration carry out the signals collecting amplifier circuit of hierarchical detection, to the signal gathering unit circuit and the open sensor signal gathering unit circuit of whether short circuit failure detection of sensor itself;

The output terminal of C, single-chip microcomputer is connecting the alerting signal output circuit.Described alerting signal output unit is respectively luminotron output and hummer HTD1 output, relay switch RLY1 output, the triode T1 open collector of three luminotron LED2, LED3 and LED4 composition and exports.

Combustible gas leakage concentration is carried out the amplifier circuit that the signals collecting amplifier circuit of hierarchical detection is made up of operational amplifier U1A and resistance R 5, R6, R7, capacitor C 3, the positive input two ends of amplifier U1A are connecting R5, C3, its reverse input end is connecting R6, R7, and its output terminal is connecting the single-chip microcomputer input port;

The open sensor signal gathering unit is made up of operational amplifier U1C and resistance R 2, R11, R12, R13 and sensor internal resistance respectively, and the end of R12, R13 is connected with the positive input of U1C, another termination power of R12, R13 other end ground connection; One end of R11 and sensor internal resistance is connected with the reverse input end of U1C, R11 other end ground connection, and the other end of sensor internal resistance is connected with R2, and the R2 other end is connected with the power supply unit output terminal, and the output terminal of U1C connects the single-chip microcomputer input end;

Signal gathering unit to whether short circuit failure detection of sensor itself is made up of operational amplifier U1D and resistance R 15, R16, R17, R18 and fuse FUSE1 respectively, the end of R17, R18 is connected with the positive input of U1D, another termination power of R17, the other end ground connection of R18; The end of R15, R16 is connected with the reverse input end of U1D, and the other end of R15 is connected with the power supply unit output terminal, the other end ground connection of R16; The output terminal of U1D connects the single-chip microcomputer input end.

During this device work, from the detection signal of sensor positive input (pin 3) through resistance R 5 and C3 input operational amplifier U1A, be level signal, can rise gradually with gas leakage concentration in certain zone and raise, after operational amplifier U1A amplifies, an input port P1 by resistance R 8 current limlitings input single-chip microcomputer U2, differentiate the height of the gas leakage concentration that this sensor is gathered by single-chip microcomputer, and the warning limit value of the combustible gas leakage that relatively sets by single-chip microcomputer, suitably output alarm signal or cue.When sensor failure, LED2 flicker, triode T1 conducting are reported to the police.

If detector adopts two sensors, then increase by one group and the identical circuit of said structure.

When sensor sample arrives the gas leakage signal, one of operational amplifier U1A output terminal output is the rising level with the rising gradually of gas leakage concentration, deliver to the another one input port P2 of single-chip microcomputer U2 through another current-limiting resistance R7, differentiate the height of the gas leakage concentration that this sensor is gathered by single-chip microcomputer, and the warning limit value of the combustible gas leakage that relatively sets by single-chip microcomputer, when inflammable gas was the severe leakage, hummer HTD1 hurriedly rang, LED3 glimmers, triode T1 conducting is reported to the police; During for slight the leakage, the slow sound of hummer HTD1 is rung, LED4 glimmers, relay R LY1 adhesive work, as opens exhaust fan or range hood.If leak the interference of illusion, the time of its effect is mostly very brief, and the intensity of effect is all had any different with the severe incident of leakage, therefore can carry out appropriate signals by single-chip microcomputer and filter, promptly intelligent the processing is considered as without exception slight incident of leakage takes place and carries out scene and point out.

In a word, form the leakage signal collecting unit by the forward voltage amplifier circuit that sensor circuit, operational amplifier are connected into, gather selectively according to the difference warning limit value (leakiness parameter) that sets, in real time the leakiness of the on-the-spot inflammable gas of monitoring leakage, leakage illusion incident.

When short circuit sensor, certainly will cause fuse FUSE1 fusing open circuit, the voltage of the reverse input end pin 13 of operational amplifier U1D must equal or approach zero, the comparer counter-rotating, the input port P4 that its output terminal is given single-chip microcomputer U2 through resistance R 19 realizes the caused failure event of detecting sensor short circuit with a high level.

Do not lose efficacy when inserting sensor or open sensor, can cause voltage rising between resistance R 2 and the R11, the voltage that is the reverse input end pin 9 of operational amplifier U1C rises, comparer is counter-rotating therefore, the input port P3 that its output terminal is given single-chip microcomputer U2 through resistance R 14 is with a high level, realizes the detecting sensor caused failure event of opening a way.

Thus, sensor circuit and operational amplifier U1 and peripheral circuit thereof etc. have been formed multiple signal collecting unit circuit.

In signal analysis, control unit circuit, utilize the input port of 3 to 6 I/O mouths of single-chip microcomputer as acquired signal; When all ports detected any signal, single-chip microcomputer all can activate corresponding program automatically, sees Fig. 3, and the level signal that institute's input port receives is carried out intelligent screening, analysis and intelligent management; According to the varying level signal that each input port received, " screening " goes out " useful " signal, automatically change corresponding warning subroutine over to, drive peripheral circuit by several output ports, utilize other 6 output ports as the alarm signal output ends mouth, see Fig. 2, under the effect of peripheral circuit, do to connect and driven for emitting lights pipe LWD2, LED3, LED4, hummer HTD1, relay R LY1 and wireless transmitter module JK2 etc.

Claims

1, combustible gas leakage detector, its circuit structure comprises power circuit and signal acquisition circuit, it is characterized in that:

2, combustible gas leakage detector according to claim 1 is characterized in that:

3, combustible gas leakage detector according to claim 1 is characterized in that: described alerting signal output unit is respectively more than one luminotron output and hummer output, relay switch output, transistor collector open circuit are exported.