CN202533196U

CN202533196U - Thermistor detector

Info

Publication number: CN202533196U
Application number: CN2012200725248U
Authority: CN
Inventors: 张永清; 吴铭钻
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-03-01
Filing date: 2012-03-01
Publication date: 2012-11-14
Anticipated expiration: 2022-03-01

Abstract

The utility model relates to a thermistor detector. A series circuit consisting of a thermistor Rt and a first resistor R1 is in parallel connection with a series circuit consisting of a potentiometer W and a second resistor R2 to form a resistive bridge. The first resistor R1 and the second resistor R2 are grounded. The output end of the thermistor Rt is connected with the base of a second transistor Q2, the output end of the potentiometer W is connected with the base of a first transistor Q1, the emitter of the first transistor Q1 is connected with the emitter of the second transistor Q2 to form a differential amplifier, and the collector of the second transistor Q2 is connected to a FDD-5 transmitter module IC2 through a third transistor Q3. According to the detector, an ordinary thermistor having a negative temperature coefficient is used to monitor the increment of the environmental temperature in fire conditions, and an alarm signal is sent to a fire protection control room or a duty room through a wireless transmitter module, so advantages of simple circuit structure, reliable operation, low cost, less components and easy fabrication are realized, so that the detector is applicable to places, such as a family, a small warehouse, a factory workshop, etc., as a fire alarm device.

Description

A kind of thermistor detector

Technical field

The utility model relates to a kind of detector, particularly be a kind of thermistor detector.

Background technology

The annual fire of China is all in rising trend; Country has put into effect relevant laws and regulations, and its most measure all adopts fire detector to detect as burning things which may cause a fire disaster, and fire detector is of a great variety; But all need be through wired mode networking; And price is more expensive, also needs the professional person to debug, and increases the cost of labor expense.

The utility model content

The purpose of the utility model is to overcome above-mentioned deficiency, and a kind of thermistor detector is provided.

The utility model solves the technical scheme that its technical matters adopted: a kind of thermistor detector; Form resistance bridge by the thermistor Rt of the common negative temperature coefficient series circuit of parallelly connected again potentiometer W and second resistance R 2 of connecting after first resistance R 1; First resistance R 1 and second resistance R, 2 ground connection; The output terminal of said thermistor R t connects the base stage of transistor seconds Q2; The output terminal of potentiometer W connects the base stage of the first transistor Q1; The emitter of the emitter of the first transistor Q1 and transistor seconds Q2 connects and composes differential amplifier, and the collector of said transistor seconds Q2 is connected to FDD-5 transmitter module IC2 through the 3rd transistor Q 3, and FDD-5 transmitter module IC2 sends modulated frequency electromagnetic waves to JDD-5 receiver module IC1.

The emitter of said the first transistor Q1 is connected stake resistance the 4th resistance R 4 with the emitter of transistor seconds Q2, the collector of the first transistor Q1 connects the 3rd resistance R 3, and the collector of transistor seconds Q2 connects the 5th resistance R 5.

The collector of said the 3rd transistor Q3 is connected to the base stage of triode VT1 through current-limiting resistance R6, divider resistance R7, the grounded emitter of triode VT1, and its collector is connected to FDD-5 transmitter module IC2.

The audio signal output end of said JDD-5 receiver module IC1 is connected with D.sp. Y, and its data output end is connected with LED 2.

Through adopting above-mentioned technical scheme; The beneficial effect of the utility model is: the monitoring that environment temperature raise when the utility model utilized the thermistor of common negative temperature coefficient that fire is taken place; And send alerting signal to fire protection control room or duty room through wireless transmitter module; Its circuit structure is simple, reliable operation, cost, components and parts are prone to system less, is applicable to that mineral wools such as family, small depot, factory floor report to the police.

Description of drawings

Fig. 1 is the circuit theory diagrams of the utility model;

Fig. 2 is the circuit theory diagrams of the utility model JDD-5 receiver module.

Embodiment

Like Fig. 1, shown in Figure 2; A kind of thermistor detector of the utility model; Form resistance bridge by the thermistor Rt of the common negative temperature coefficient series circuit of parallelly connected again potentiometer W and second resistance R 2 of connecting after first resistance R 1; First resistance R 1 and second resistance R, 2 ground connection; The output terminal of said thermistor Rt connects the base stage of transistor seconds Q2, and the output terminal of potentiometer W connects the base stage of the first transistor Q1, and the emitter of the emitter of the first transistor Q1 and transistor seconds Q2 connects and composes differential amplifier; The collector of said transistor seconds Q2 is connected to FDD-5 transmitter module IC2 through the 3rd transistor Q 3, and FDD-5 transmitter module IC2 sends modulated frequency electromagnetic waves to JDD-5 receiver module IC1.

The emitter of said the first transistor Q1 is connected stake resistance the 4th resistance R 4 with the emitter of transistor seconds Q2; The collector of the first transistor Q1 connects the 3rd resistance R 3; The collector of transistor seconds Q2 connects the 5th resistance R 5; The collector of said the 3rd transistor Q3 is connected to the base stage of triode VT1 through current-limiting resistance R6, divider resistance R7, the grounded emitter of triode VT1, and its collector is connected to FDD-5 transmitter module IC2; The audio signal output end of said JDD-5 receiver module IC1 is connected with D.sp. Y, and its data output end is connected with LED 2.

When normal temperature, A, 2 signals of B are imported respectively by the base stage of the first transistor and transistor seconds Q2, and A, 2 current potentials of B equate; After amplifying; By the collector output noble potential of transistor seconds Q2, the 3rd transistor Q3 ends, and triode VT1 also ends simultaneously; FDD-5 transmitter module IC2 is not because of there being trigger pip, and do not send alerting signal.

When fire took place, the environment temperature of thermistor Rt raise rapidly, made its resistance descend; When reaching uniform temperature, the resistance of thermistor Rt is little as to make the electric bridge out of trim, and A point current potential rises gradually; Make the 3rd transistor Q3 conducting, the output high level signal is behind current-limiting resistance R6, divider resistance R7; Triode VT1 also gets into conducting state, makes FDD-5 transmitter module IC2 obtain trigger pip, and this signal is input to the 2nd pin of FDD-5 transmitter module IC2; And deliver to its 3rd pin modulation signal input end CP, and the high-frequency signal of emission is modulated, antenna TX promptly launches modulated frequency electromagnetic waves to the JDD-5 receiver module; The 4th pin audio signal output end CPA of JDD-5 receiver module IC1 directly drives common electrical dynamic formula loudspeaker Y and sends chimes of doom; Its 2nd pin data output end output high level makes LED 2 get the electric luminous indication of lighting simultaneously, representes breaking out of fire, thereby reminds the fire extinguishing personnel to do corresponding fire-fighting work.

An above-described preferred embodiment that is merely the utility model can not limit the scope that the utility model is implemented, and every equalization of being done according to the utility model claim changes and decorates, and all should still belong in the scope that the utility model contains.

Claims

1. thermistor detector; It is characterized in that: form resistance bridge by the thermistor Rt of the common negative temperature coefficient series circuit of parallelly connected again potentiometer W and second resistance R 2 of connecting after first resistance R 1; First resistance R 1 and second resistance R, 2 ground connection; The output terminal of said thermistor Rt connects the base stage of transistor seconds Q2; The output terminal of potentiometer W connects the base stage of the first transistor Q1; The emitter of the emitter of the first transistor Q1 and transistor seconds Q2 connects and composes differential amplifier, and the collector of said transistor seconds Q2 is connected to FDD-5 transmitter module IC2 through the 3rd transistor Q3, and FDD-5 transmitter module IC2 sends modulated frequency electromagnetic waves to JDD-5 receiver module IC1.

2. thermistor detector according to claim 1; It is characterized in that: the emitter of said the first transistor Q1 is connected stake resistance the 4th resistance R 4 with the emitter of transistor seconds Q2; The collector of the first transistor Q1 connects the 3rd resistance R 3, and the collector of transistor seconds Q2 connects the 5th resistance R 5.

3. thermistor detector according to claim 1; It is characterized in that: the collector of said the 3rd transistor Q3 is connected to the base stage of triode VT1 through current-limiting resistance R6, divider resistance R7; The grounded emitter of triode VT1, its collector are connected to FDD-5 transmitter module IC2.

4. thermistor detector according to claim 1 is characterized in that: the audio signal output end of said JDD-5 receiver module IC1 is connected with D.sp. Y, and its data output end is connected with LED 2.