CN2240753Y

CN2240753Y - Domestic gas leakage alarm device

Info

Publication number: CN2240753Y
Application number: CN 95236462
Authority: CN
Inventors: 孙国元
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-03-27
Filing date: 1995-03-27
Publication date: 1996-11-20
Anticipated expiration: 2005-03-27

Abstract

The utility model discloses a domestic gas leakage alarm device. The utility model mainly solves the problems of the existing alarm that the design of the opening is not proper, the burnt gas is difficult to touch a gas sensor, the response time is long, and the sensitivity is low. The cabinet of the alarm device is provided with an air flow hole with small upper part and big lower part, and the environmental air can flow into the alarm device; the bottom of the casing is provided with an adjusting button to improve the alarm sensitivity; the alarm circuit is composed of a power supply, a gas sensor, a detecting circuit, an audio oscillator, and an electric acoustic device. The gas leakage alarm and the gas sensor failure alarm can be realized, and the utility model can also be used as the door bell. The utility model is suitable for the ordinary family, and one machine has multiple functions.

Description

The household gas leakage alarm

The utility model relates to a kind of inflammable gas detection alarm device, refers to a kind of household gas leakage alarm particularly.

Present existing household gas leakage alarm, the circulation of environmental gas is not considered in the design of its openings in enclosure.Heater elements such as power transformer, gas sensor are installed in the casing, its inner air themperature is higher than the outside, therefore the gas in the external environment condition often is difficult to enter enclosure interior by the perforate on casing surface, has so just influenced the sensitivity and the response time of alarm; After alarm used a period of time, its sensitivity also will descend with the pollution of environment, the reliability variation simultaneously.In addition, existing alarm does not generally have the gas sensor breaking alarming, and detectors is single.

The purpose of this utility model will provide a kind of adaptation housing inside and outside gas flow exactly, and the response time is fast, and is highly sensitive, the household gas leakage alarm of being convenient to regulate.

Be the household gas leakage alarm of realizing that this purpose the utility model is designed, have the suspension type casing and be installed in casing interior power supply and main circuit, casing is made of cover 1 and bottom 2, be furnished with power light VD3 and alarm lamp VD4 and speaker openings in the main circuit on the cover 1, on the bottom 2 suppending hole arranged.Main circuit is made up of gas sensor, detection comparator circuit, alarm unit.Have combustion gas air admission hole 4 at bottom of shell, the top has combustion gas venthole 3, and the aperture area of air admission hole 4 forms up-small and down-big chimney effect and is beneficial to gas flow greater than the aperture area of venthole 3.The opening part design of air admission hole 4 has alarm sensitivity adjusting knob RP, can regulate its sensitivity outside casing.

Advantage of the present utility model is that casing only adopts perforate up and down, and the heat that casing internal heat generation element produces makes air heating rising in the shell, has accelerated the environment cold air and has sucked from the bottom, has improved the response time of alarm; Simultaneously can the variation according to environment in the casing outside, the degree of aging flexible alarm sensitivity of gas sensor has improved the reliability of alarm work.And this device can monitor whether operate as normal of gas sensor, but and the double as doorbell use.

Below in conjunction with embodiment the utility model is described in further detail:

Fig. 1 is a casing structure synoptic diagram of the present utility model;

Fig. 2 is the upward view of Fig. 1;

Fig. 3 is an electronic circuitry of the present utility model.

Being furnished with power light among the figure on the casing cover 1 respectively is that green LED VD3 and alarm lamp are red light emitting diodes VD4, and speaker openings, top venthole 3 is made up of some strip gabs, bottom inflow hole 4 then is an oblong openings, and the big 1-3 of the aperture area of its open area ratio venthole 3 doubly.The design of bottom opening place has sensitivity adjusting knob RP, can regulate the sensitivity of alarm outside casing easily.

Power supply adopts 220 volts of Alternating Current Power Supplies, 2 * 9 volts of transformer-secondary voltages, center tap ground connection in the casing.Form full-wave rectifying circuit by diode VD1, VD2, E is+6 volts through regulator block IC3 voltage stabilizing out-put supply, and resistance R 1 and light emitting diode VD3 are serially connected between power supply E and the ground.The heater strip one termination power E of gas sensor Q, ground connection behind the other end series resistor R2, its serial connection point connects the positive input of comparer IC1-3, one termination power E of resistance R 11, reverse input end and the resistance R 12 of another termination comparer IC1-3, the other end ground connection of resistance R 12, the output terminal of comparer IC1-3 links to each other with diode VD7 with resistance R 13, and the other end of resistance R 13 and diode VD7 connects 1 pin of power supply E and oscillator IC2 respectively.The A termination power E of gas sensor Q, B terminating resistor R3, R4, the other end ground connection of resistance R 3, the other end of R4 then connects the reverse input end of capacitor C 3 and comparer IC1-1, the other end ground connection of capacitor C 3, one termination power E of resistance R 5, the positive input of another termination comparer IC1-1 and the upper end of sensitivity controller RP, the tip side of RP and lower end ground connection; One termination power E of resistance R 6 connects the output terminal of comparer IC1-1 behind the other end serial connection alarm lamp VD4, connect 1 pin of oscillator IC2 behind this output terminal serial connection diode VD5.One termination power E of resistance R 7,7 pin of other end connecting resistance R8, capacitor C 4 and oscillator IC2, the other end ground connection of resistance R 8,

capacitor C

4,4, the 5 pin cross-over connection resistance R 9 of oscillator IC2,6 pin ground connection, connect the base stage of triode VT behind the 8 pin serial connection diode VD6, the grounded emitter of three utmost point VT meets power supply E behind the collector series connection loudspeaker BL; Capacitor C 2 one termination power E, other end ground connection.Constitute the gas leakage alarm part thus.

For realizing the purpose of a tractor serves several purposes, in the above-mentioned main circuit also additional design one doorbell circuit, one termination power E of its resistance R 14, other end connecting resistance R15, the positive input of R16 and comparer IC1-2, the other end ground connection of resistance R 16, the output terminal of comparer IC1-2 and resistance R 10, R17, the other end of R18 and R15, one end of capacitor C 5 links to each other, the base stage of another termination triode VT of resistance R 10 and capacitor C 5, link to each other with power supply E behind the other end serial connection bell button SB of resistance R 18, the reverse input end of another termination comparer IC1-2 of resistance R 17 and an end of capacitor C 6, the other end ground connection of capacitor C 6.

The regulator block IC3 of above-mentioned alarm can select LM7806 for use, oscillator IC2 selects 5G0602 for use, detect and relatively to adopt special integrated package LM339 as comparer, in 4 independently comparers are arranged, this device has adopted three, i.e. IC1-1 among Fig. 3, IC1-2 and IC1-3.During alarm work, regulate sensitivity adjusting button RP earlier and make the voltage of the voltage of comparer IC1-1 positive input a little more than reverse input end in peace and quiet air, comparer IC1-1 exports noble potential, the 1 pin noble potential of oscillator IC2, IC2 failure of oscillation alarm free.When containing inflammable gas, smog etc. in the air, current potential on the resistance R 3 rises, the current potential of comparer IC1-1 reverse input end rises, when its current potential rising is higher than positive input, the IC1-1 counter-rotating is promptly exported electronegative potential, oscillator IC2 starting of oscillation, loudspeaker sends chimes of doom, and VD4 is luminous for the indication red light of reporting to the police simultaneously.The effect of resistance R 4, capacitor C 3 has been certain time-lag actions; Prevent that instantaneous interference from waiting triggering to report to the police as smoking.Comparer IC1-3 is used for monitoring the work of gas sensor Q heater strip, and when heater strip opened circuit, comparer IC1-3 counter-rotating caused chimes of doom, did not just have luminous indication this moment, was convenient to both differences.And comparer IC1-2 is connected into oscillatory circuit, and when bell button SB was closed, comparer IC1-2 starting of oscillation produced the audio oscillation about 1000HZ, and its oscillation frequency can be adjusted by capacitor C 6, as the source of sound of electronic door bell.Doorbell sound and chimes of doom are completely different, can not cause misleading.

Claims

1, a kind of household gas leakage alarm, comprise the suspension type casing and be installed on its interior power supply and main circuit, be furnished with power light VD3 and alarm lamp VD4 and speaker openings in the main circuit on the casing cover (1), main circuit is by gas sensor, detect comparator circuit, alarm unit is formed, it is characterized in that: bottom of shell has combustion gas air admission hole (4), the top has combustion gas venthole (3), the aperture area of air admission hole (4) is greater than the aperture area of venthole (3), and air admission hole (4) opening part is provided with the alarm sensitivity adjusting knob RP that can regulate sensitivity outside shell.