CN2044087U

CN2044087U - Gas alarm controller

Info

Publication number: CN2044087U
Application number: CN 88216450
Authority: CN
Inventors: 周少力; 于宗明; 孙向群
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-12-28
Filing date: 1988-12-28
Publication date: 1989-09-06

Abstract

The utility model relates to a gas alarm controller and belongs to the technical field of an alarm device, comprising a power supply, a fume-electricity transducer, a comparison oscillator, and an output control device. The utility model chooses a special gas sensor as a sensor to detect the interior gas content. The sensitivity of the sensor is high. An NE555 integrated circuit is adopted in the comparison oscillator, which can save components. Twenty components are used only in one device. The utility model has the advantages that the gas alarm controller does not need to be adjusted after the gas alarm controller is assembled, the production cost is low, the cost performance is high, the device can be used at the combustible and explosive environment because of no touch and no spark. The utility model has four functions of sound, light alarm, external control, and the conversion of automatic, manual control.

Description

Gas alarm controller

At present, the various gas leak detectors of on newpapers and periodicals, publishing, the aspects such as development and use at circuit structure, components and parts come with some shortcomings, for example " electronics newspaper " 88 year the 39th phase goes up " the household fuel gas alarm " introduced and just exists complicated shared 41 elements of circuit, function singleness; Circuit adjustment trouble during batch process, to the coherence request height of element, increases shortcomings such as production cost.

The purpose of this utility model is a kind of novel gas alarm controller of design.Have sound, light warning, external control, automatic/hand control transformation, four kinds of functions.Contactless, no-spark can be used in inflammable, explosive environment, and the simple and reliable used element of circuit is few, need not adjust substantially after the assembling, has higher performance.

The utility model is made up of power supply, pneumo-electrical convertor, comparison oscillator and o controller, and its signal annexation is: the input end of the output termination comparison oscillator of pneumo-electrical convertor, the input end of the output termination o controller of comparison oscillator.Be connected to three end integrated voltage stabilizers in the power circuit of the present utility model, be connected to gas sensor, light emitting diode in the pneumo-electrical convertor, adjustable resistance and thermo-compensator, comparison oscillator is selected integrated circuit for use, selects bidirectional triode thyristor in the o controller for use and is provided with piezoelectric buzzer.The utlity model has following characteristics:

1, select the sensor of special-purpose gas sensor for use as gas content in the sensing chamber, highly sensitive;

2, circuit adopts three end integrated voltage stabilizers and thermo-compensator to make stable work in work;

3, comparison oscillator is selected integrated circuit for use, has saved element, and complete machine is only used 20 elements, and need not adjust substantially after the assembling;

4, it is contactless to select for use bidirectional triode thyristor to realize, no-spark is switched on or switched off the function of vent fan power supply automatically;

5, light emitting diode can send visual alarm, and piezoelectric buzzer can send acoustic alarm signal;

6, hand switch control automatic/hand conversion of operation state under normal circumstances can be used vent fan separately.

Describe concrete structure of the present utility model and principle of work in detail below in conjunction with drawings and Examples.

Accompanying drawing 1 is the utility model circuit block diagram, and among the figure, (1) is power supply, and (2) are pneumo-electrical convertor, and (3) are comparison oscillator, and (4) are o controller; Accompanying drawing 2 is the utility model circuit theory diagrams, power supply among the figure (1) comprises piezoelectric transformer B, bridge rectifier D 1-D4, filter capacitor C1, be connected with three end integrated voltage stabilizer IC1 at bridge rectifier D1-D4 output terminal, pneumo-electrical convertor (2) comprises gas sensor QM, the adjustable resistance RW that connects with gas sensor QM, compensating resistance RT and be connected the light emitting diode FG1 that A is ordered on the adjustable resistance RW travelling arm, comparison oscillator (3) comprises integrated circuit (IC) 2 and resistance R 1, capacitor C 2, o controller (4) comprises coupling capacitance C3, bidirectional triode thyristor KG, light emitting diode FG2, resistance R 2, hummer YD, hand switch K1 and output control lead-in wire L1, L2, be serially connected in after light emitting diode FG2 and resistance R 2 parallel connections in the control utmost point loop of bidirectional triode thyristor KG, hummer YD is connected between the negative pole and ground of coupling capacitance C3, the positive pole of coupled circuit C3 is connected on the output terminal of integrated circuit (IC) 2, hand switch K1 is attempted by between the negative electrode and anode of bidirectional triode thyristor KG, output control lead-in wire L1, L2 connects with external vent fan by bidirectional triode thyristor KG.

Embodiment:

The elementary input AC 220V of power transformer B voltage, secondary output AC 10V voltage, bridge rectifier D 1-D4 selects the 1N4001 commutation diode for use, filter capacitor C1 selects 470 microfarads for use, the electrolytic vessel of withstand voltage 25V, three end integrated voltage stabilizer IC1 select the CW7805 of voltage stabilizing+5 volt for use, and gas sensor QM selects HQ-5 type, resistance R 1=51K for use.Adjustable electric RW=4.7K, thermo-compensator RT=3K, current-limiting resistance R2=300 ohm, oscillating capacitance C2=0.02 microfarad, withstand voltage 25V, coupling capacitance C3=10 microfarad, withstand voltage 25V, light emitting diode FG1, FG2 starting voltage 3V, integrated circuit (IC) 2 is selected NE555 for use, bidirectional triode thyristor KG is withstand voltage 400 volts, 1 ampere of rated operational current, hummer YD are selected the piezoelectric ceramic piece of 25 millimeters of diameters for use.

Principle of work of the present utility model is: connect and exchange 220 volts of power supplys, 10 volts of voltages of transformer B time level output AC, through bridge rectifier D 1-D4 full-wave rectification, capacitor C 1 filtering, output DC voltage VC over the ground, one tunnel working power as gas sensor QM and integrated circuit (IC) 2, export 5 volts DC voltage VH over the ground after another Lu Jingsan end integrated voltage stabilizer IC1 voltage stabilizing, be the filament operating voltage of gas sensor QM.At the filament pre-heating of gas sensor after 10 minutes, complete machine enters normal operating conditions, levelling RW, making A point current potential is 2 volts, when normal operating conditions, the 3a pin of IC2 is a noble potential, by resistance capacitor C 2 is charged, light emitting diode FG1 is clamped at about 5 volts B point current potential, not starting of oscillation of IC2, not conducting of bidirectional triode thyristor KG, noiseless, light is reported to the police, when indoor when gas leakage being arranged and making that gas content reaches warning concentration in the gas-sensitive head QM surrounding air (warning concentration is transferred to 1400PPM), A point current potential rises gradually, this moment, B point current potential also rose thereupon, when B point current potential reaches the voltage of 2/3VC, and the IC2 starting of oscillation, the light emitting diode FG1 that play clamping action this moment ends, make IC2 keep vibration, and export continuous square-wave pulse, by coupling capacitance C3 by the 3a end of IC2, current-limiting resistance R2, trigger bidirectional triode thyristor KG, make the bidirectional triode thyristor conducting, connect vent fan, while light emitting diode FG2, piezoelectric buzzer YD sends light respectively, acoustic alarm.When removing the dangerous condition, gas concentration drops to warning concentration when following, A point current potential drops to 2 volts thereupon gradually, B point current potential is clamped at about 5 volts by the FG1 light emitting diode, returns to normal condition, the IC2 failure of oscillation, the 3a end output noble potential of IC2, bidirectional triode thyristor KG turn-offs, and vent fan quits work, and sound, visual alarm are removed.

When the needs scavenger fan is opened separately, can make its closure by hand switch K1, connect vent fan, when K1 disconnected, this machine just entered automatic controlling alarm state.

Claims

1, a kind of gas alarm controller, include power supply (1) and pneumo-electrical convertor (2) and it is characterized in that also including comparison oscillator (3) and o controller (4), its signal annexation is the input end of the output termination comparison oscillator (3) of pneumo-electrical convertor (2), the input end of the output termination o controller (4) of comparison oscillator (3).

2,, it is characterized in that bridge rectifier D1-D4 output terminal is connected with three end integrated voltage stabilizer IC1 in described power supply (1) circuit according to the said gas alarm controller of claim 1.

3, according to the said gas alarm controller of claim 1, it is characterized in that described pneumo-electrical convertor (2) comprises gas sensor QM, adjustable resistance RW that connects with gas sensor QM and thermo-compensator RT are connected the light emitting diode FG1 on the adjustable resistance RW travelling arm A point.

4, according to the said gas alarm controller of claim 1, it is characterized in that described o controller (4) comprises coupling capacitance C3, bidirectional triode thyristor KG, light emitting diode FG2, resistance R 2, hummer YD, hand switch K1 and output control lead-in wire L1, L2, be serially connected in the control loop of bidirectional triode thyristor KG after light emitting diode FG2 and resistance R 2 parallel connections, hummer YD is connected between the negative pole and ground of coupling capacitance C3, the positive pole of coupling capacitance C3 is connected on the output terminal of integrated circuit (IC) 2, hand switch K1 is attempted by between the anode and negative electrode of bidirectional triode thyristor KG, output control lead-in wire L1, L2 connects with the vent fan of outside by bidirectional triode thyristor KG.

5, according to the said gas alarm controller of claim 1, it is characterized in that described comparison oscillator (3) comprises integrated circuit (IC) 2 and resistance R 1, capacitor C 2, integrated circuit is selected NE555 for use.