CN101383075A - Ultraviolet-infrared composite flame detection alarm with optical self-checking function and method - Google Patents

Abstract

The invention relates to an ultraviolet-infrared composite flame detection alarm device with an optical self-check function and a method thereof, and is characterized in that an infrared luminescent tube is connected with a band-pass amplifier circuit; an ultraviolet luminescent tube and an ultraviolet photoelectric detection tube are connected with an intelligent ultraviolet driving and signal sampling circuit; Connect an ultraviolet extraction and conversion circuit at the output end of the detector power conversion circuit, connect the detector data main processing circuit at the output end of the intelligent ultraviolet drive and signal sampling circuit; The output end of the detector data main processing circuit is connected to the band-pass amplifier circuit; the output end of the detector data main processing circuit and the detector power conversion circuit is connected to the detector isolated power supply 485 communication circuit, the detector 4-20mA signal output circuit and the detector relay output circuit. The invention has the advantages of judging the flame signal through the combination of ultraviolet and infrared, reducing the false alarm rate and improving the adaptability of the detector to the use environment to achieve a higher degree of intelligence.

Description

Ultraviolet-infrared composite flame detection alarm with optical self-checking function and method

technical field

The invention belongs to the field of automatic fire detection and alarm, in particular to an ultraviolet-infrared composite flame detection alarm with an optical self-check function and a method thereof.

Background technique

In the early days, ordinary ultraviolet or single-band infrared flame detectors were used internationally as a means to protect the fire safety of large spaces and underground buildings. Poor, prone to false alarms. In recent years, some people at home and abroad have studied the use of CCD flame imaging technology to detect flames. Due to the lack of basic theoretical research on the corresponding early fire image detection, the development of fire image technology has been limited to a certain extent. Therefore, in recent years, Japan, Switzerland and other countries have successively developed and successfully used dual-band infrared flame detectors for fire safety protection of large spaces and underground buildings. It can further suppress the interference of environmental interference signals, improve the reliability of the detector, and become the latest product for protecting the fire safety of underground and large space buildings.

With the rapid development of my country's economic construction, the number of large space buildings and underground buildings is increasing, such as large public entertainment places, large warehouses, large bazaars, hangars, garages, oil depots, waiting halls and waiting halls, underground tunnels , subway station road, underground large parking lot and underground commercial street, etc. Because the interior of this type of building is often elevated and spanned, the smoke diffusion at the initial stage of the fire is greatly affected by the air-conditioning and ventilation systems installed inside the building. The fire spreads rapidly, the generated smoke is highly toxic, and it is difficult to evacuate and rescue people. Once a fire occurs, it often causes great economic losses and adverse social impacts. Therefore, underground and large-space buildings have become one of the key objects of fire protection. .

Due to the particularity of underground and large-space buildings, ordinary point-type smoke and temperature-sensing fire detection and alarm systems cannot quickly collect information on changes in smoke temperature emitted by fires, so it is difficult to meet the requirements for early detection and prediction of such building fires. Common ultraviolet and single-band infrared flame detectors were used early in the world as a means of protecting large-space buildings. However, due to limitations of technical and technological levels, the ability to suppress environmental interference is poor in practical applications, and errors are prone to occur. Call the police.

Contents of the invention

Aiming at the problems existing in the prior art, the present invention provides an ultraviolet-infrared composite flame detection and alarm device with an optical self-inspection function and a method, which comprehensively adopts dual information sensing technology of flame ultraviolet and infrared spectrum models, and two waveband optimization technologies and integrated fire recognition software algorithms.

The ultraviolet-infrared composite flame detection alarm device with optical self-checking function of the present invention includes ultraviolet protection lens, infrared protection lens, band-pass amplifier circuit, data main processing circuit, intelligent ultraviolet driving and signal sampling circuit, controller power conversion circuit , controller relay output circuit, controller 4-20mA signal output circuit, ultraviolet extraction and conversion circuit, ultraviolet light-emitting tube, infrared light-emitting tube, ultraviolet photoelectric detection tube, controller isolated power supply 485 communication circuit, external reflector and structural fixing device ; A reflector is installed behind the UV protection lens and the infrared protection lens; the infrared luminous tube is connected with the band-pass amplifier circuit; The terminal is connected to an ultraviolet extraction and conversion circuit, and the output end of the intelligent ultraviolet drive and signal sampling circuit is connected to the detector data main processing circuit; the detector external signal input detection and detector self-inspection infrared LED drive circuit and detector data main processing circuit The output end of the circuit is connected with the band-pass amplifier circuit; the output end of the detector data main processing circuit and the detector power conversion circuit is connected with the detector isolated power supply 485 communication circuit, the detector 4-20mA signal output circuit and the detector relay output circuit.

The detector self-inspection process of the present invention: through the internal timer, when the cumulative time reaches the preset time, the detector detects whether there is a flame signal in the signal of the ultraviolet sensor, and if there is no flame signal, starts the ultraviolet light-emitting tube and detects whether the ultraviolet sensor is normal If it is normal, it will enter to detect the infrared sensor, if it is not normal, it will report the failure of the ultraviolet detector; at the same time, the detector will detect whether there is a flame signal in the signal of the infrared sensor, if there is no flame signal, it will start the infrared light-emitting tube, and check whether the infrared sensor is normal, and if it is normal, it will enter the fire alarm Judgment process, if abnormal, report infrared detector failure.

The casing of the present invention includes a back cover, a front cover, a housing, a front panel, a reflector, an ultraviolet protection lens, an ultraviolet detection plate, an infrared detection plate and an infrared protection lens, and the infrared detection plate, the system and the ultraviolet detection plate are fixed on the front plate , the detector output interface board is fixed on the back cover part of the shell, and the front panel and the back cover part are connected by signal lines.

The intelligent ultraviolet drive and signal sampling circuit of the present invention adopts 8-bit single-chip microcomputer U12 as the ultraviolet drive, controls the single-input double-output step-up transformer T1 driven by the three-stage tube N1 through PIN7, and obtains the ultraviolet photoelectric tube through the fast recovery diode and resistance-capacitance coupling The required high voltage is driven by pulses; it communicates with the U8 main processor through PIN4-63 pins, and controls different UV driving modes according to different signals of the main processor. The ultraviolet photoelectric detection tube and the ultraviolet luminescent tube are powered by a step-up transformer.

The band-pass amplifying circuit of the present invention is mainly divided into infrared signal extraction, infrared sensor amplification, gain adjustment, threshold voltage adjustment and signal conversion circuit. The infrared signal extraction circuit is a power supply connected to PIN3 of U5 through infrared sensor U1 and then grounded through R1, PIN1 and PIN2 of U5 are short-circuited, and dynamic threshold technology is used; U5B, U6A, and U6C form an infrared sensor amplification circuit, and digital zoom technology is used ; U6C and 1 channel of the dual digital potentiometer U7 form a gain adjustment circuit; U6B and 0 channel of the dual digital potentiometer U7 form a threshold voltage adjustment circuit; the signal is composed of D3, R6, D4, R38, R14, C45, and E6 conversion circuit.

The detector relay output circuit of the present invention adopts passive relay signal output; the detector 4-20mA signal output circuit outputs the pulse width modulation signal through the single-chip microcomputer; the detector isolation power supply 485 communication circuit adopts optocoupler, power isolation module, 485 communication chip And three momentary suppression diodes suppress the interference signal on the signal line during external communication.

The method for the ultraviolet-infrared composite flame detector of the present invention comprises the following steps;

Step 1 System initialization

Reset the system, turn off the interrupt, initialize the relay, port, RAM and timer T ₀ , T ₁ , collect the alarm setting and sensitivity setting, light the red LED for 5 seconds, and the green LED for 5 seconds, initialize AD, initialize the timer T ₂ , set Set and open the interrupt, clear the watchdog flag, and wait for the interrupt in a loop.

Step 2 Signal acquisition, realized by coding

After the _T2 timing interrupt, AD conversion is performed to obtain the signal amplitude and frequency data of the two channels. Through the interrupt judgment, perform the corresponding interrupt operation. After entering the _T2 timing interrupt service subroutine, the operation sequence is: _T2 timing interrupt initialization; fire alarm judgment; whether frequency acquisition is required; whether amplitude sampling data is required; whether comprehensive fire alarm judgment is required ; Then _T2 timing interrupt returns.

Step 3 Signal Processing

The collected data is brought into operation by algorithm, and the algorithm is used to judge whether there is a fire. The specific algorithm is as follows;

1. Infrared flame amplitude judgment

(1) Judgment based on fixed base value

When A _i -Ca≥Cb and (A _i -Ca)/n≥Cb, where n is a natural number, where Ai is the current infrared AD sampling amplitude of the flame channel, Ca is the fixed base value of the flame channel, and Cb is the fixed value of the infrared response , is the ratio of the signal amplitude increase of the channel; if this condition is met within the set number of judgments, the amplitude is judged to meet the fire alarm condition, and the judgment procedure based on the compensation base value is skipped and the flicker frequency judgment is performed; when A _i -Ca<Cb , judge based on the compensation base value;

(2) Judging based on the compensation base value

When A _i -Ca ₁ ≥ _{Cb 1} and (A _i -Ca ₁ )/n ≥ Cb ₁ , where Ca ₁ is the flame channel compensation base value, and Cb is the infrared response compensation value, the condition is met within the set judgment times Then it is judged that the amplitude meets the fire alarm condition, and the flashing frequency is judged;

2. Infrared flame frequency judgment

The average value of the frequency data of the infrared flame channel within the set judgment times is Fav, 4≤Fav≤20, and the infrared sampling frequency data of the flame channel are Fa ₀ (current), Fa ₁ , Fa ₂ ,..., Fa _i ( i=N), wherein the frequency satisfies 4≤Fa _i≤20 (i=N) for 4 consecutive times, then the flickering frequency is judged to meet the fire alarm condition.

3. Judgment of ultraviolet flame frequency signal

The average value of the frequency data of the ultraviolet flame channel in the set judgment times is Fuv, Fmin≤Fuv≤Fmax, and the frequency data of the ultraviolet flame channel are Fu ₀ (current), Fu ₁ , Fu ₂ ,... Fu _i (i= N), where the frequency satisfies Fmin≤Fa _i≤Fmax (i=N) for 4 consecutive times, then the ultraviolet flicker frequency is judged to meet the fire alarm condition.

4. Ultraviolet and infrared composite judgment.

When the infrared matches the fire alarm, the infrared fire alarm signal is output; when the ultraviolet light matches the fire alarm, the ultraviolet fire alarm signal is output; when one of the two signals matches the fire alarm signal, and the other is in the fire alarm warning state, it is paired according to the preset comparison parameters , if it meets the alarm state, it will report a fire alarm.

Step 4 Signal output

The alarm signal is output through the detector 4-20mA signal output circuit or the detector relay output circuit. If it is an alarm signal, the operation ends. If it is not an alarm signal, it enters the detector self-test.

Invention effect

1. Using intelligent ultraviolet photoelectric tube drive, using 8-bit single-chip microcomputer for separate pulse drive, can be driven in different configurations according to different detection time requirements, simplifying the original ultraviolet photoelectric tube that requires multiple chips to coordinate the drive pulse width, relatively The working mode of continuous AC power supply greatly reduces power consumption. A step-up transformer is designed to realize the use of a transformer to provide the power supply for the ultraviolet photodetector tube and the ultraviolet light-emitting tube. By cooperating with the multi-channel counting of the main processor and combining multiple sampling circuits with different signal levels, the signals of different voltage levels can be analyzed. Counting changes the current situation that the previous ultraviolet detection only counts the number of pulse signals without distinguishing the signal level.

2. Using digital zoom technology and flame frequency extraction circuit with dynamic threshold, the detector performs band-pass amplification for the infrared sensor, and adjusts the amplification gain by using the digital potentiometer, and through the amplification gain adjustment, there is a short distance during the detection process of the detector The flame signal detection of the fire provides a solution; the detector uses a digital potentiometer combined with an operational amplifier to extract the flame frequency signal, ensuring that the detector is always effective in extracting the flame signal when the background drifts in different environments.

3. The use of ultraviolet light-emitting tubes and infrared light-emitting tubes, combined with specially processed reflectors, constitutes the optical integrity of the detector, ensuring that the detector not only has the function of detecting flames, but also has the function of detecting the failure of internal sensors of the detector , and also realized the pollution detection for the detector protective lens.

4. Adopt passive relay signal output, RS485 industrial communication interface, 4-20MA signal output 3 kinds of communication methods, basically compatible with most of the controllers on the market, with good compatibility performance, using flameproof structure, suitable for various kind of industrial site.

Description of drawings

Fig. 1 is a schematic diagram of the structure of an ultraviolet-infrared composite flame detection alarm with an optical self-check function;

Figure 2 is a schematic structural diagram of an ultraviolet-infrared composite flame detection alarm system with an optical self-check function;

Fig. 3 is a block diagram of the basic design principle of the ultraviolet-infrared composite flame detection alarm with optical self-checking function;

Fig. 4 is the system flowchart of the ultraviolet-infrared composite flame detection alarm with optical self-checking function;

Fig. 5 is the infrared detection data processing flowchart of the ultraviolet-infrared composite flame detection alarm with optical self-checking function;

Fig. 6 is the fixed circuit diagram on the infrared detection board, wherein,

(a) is a detector band-pass amplifier circuit diagram;

(b) Infrared LED drive circuit diagram for detector external signal input detection and self-inspection;

(c) is the circuit diagram of the dual-color LED driver of the detector;

Fig. 7 is the fixed circuit diagram on the system and the ultraviolet detection board, wherein,

(a) is a detector power conversion circuit;

(b) is the detector data main processing circuit;

(c) is an intelligent ultraviolet driving and signal sampling circuit;

(d) is an ultraviolet sensor self-test driving circuit;

(e) an ultraviolet signal extraction and conversion circuit;

Fig. 8 is a fixed circuit diagram on the detector output interface board, wherein,

(a) It is the detector power supply polarity conversion circuit and the power supply anti-interference circuit;

(b) is the detector 4-20MA signal output circuit;

(c) isolate the power supply circuit for the detector;

(d) 485 communication circuits for the isolated power supply of the controller;

(e) is the detector relay output circuit;

In the figure, 1 is the rear cover, 2 is the housing, 3 is the front cover, 4 is the front panel, 5 is the UV protection lens, 6 is the UV detection plate, 7 is the infrared detection plate, 8 is the infrared protection lens, 9 is the reflector, 10 shells, 11 brackets, 12 detector output interface boards.

Detailed ways

As shown in Figure 1, the housing includes a rear cover, a front cover, a housing, a front panel, an ultraviolet protective lens, an ultraviolet detection plate, a reflector, an infrared detection plate and an infrared protective lens, and the infrared detection plate, the system and the ultraviolet detection plate are fixed on On the front panel, the detector output interface board is fixed on the back cover of the housing, and the front panel and the back cover are connected through signal lines. Among them, the infrared protective lens is required to be made of a material with a transmittance of 1-14 μm infrared light higher than 85%, and the environmental adaptability requires corrosion resistance, wiping, damp heat and high and low temperature. UV protective lenses are required to be made of materials with a transmittance of 200-1000nm ultraviolet light higher than 85%, and environmental adaptability requires corrosion resistance, wiping, damp heat and high and low temperature.

As shown in Figure 2 and Figure 3, the detector power conversion circuit obtains the voltage required by different circuit modules through power conversion. The +12v input terminal of the ultraviolet signal extraction and conversion circuit is connected to the +12v output terminal of the detector power conversion circuit. The 3.3v output terminal of the signal extraction and conversion circuit is connected with the +3.3v input terminal of the intelligent ultraviolet drive and signal sampling circuit; the output terminal of the intelligent ultraviolet drive and signal sampling circuit is connected with the input terminal of the detector data main processing circuit; The input end of the two-color LED drive circuit is connected to the 24v output end of the detector power conversion circuit, and the output end of the detector two-color LED drive circuit is respectively connected to the external signal input detection and self-test of the detector. The infrared LED drive circuit and the ultraviolet sensor self-test drive circuit The input end is connected; the output end of the detector external signal input detection and self-inspection infrared LED drive circuit is connected with the input end of the band-pass amplifier circuit; the output end of the band-pass amplifier circuit is connected with the input end of the detector data main processing circuit, and the detection The input end of the detector power supply polarity conversion circuit and the power supply anti-interference circuit is connected with the +24v output end of the detector power conversion circuit; the output end of the detector data main processing circuit is connected with the controller 4-20mA signal output circuit, and the controller 4- The 20mA signal output circuit is connected to the +24v output terminal of the detector power conversion circuit, and the input terminal of the detector relay output circuit is respectively connected to the output terminal of the detector data main processing circuit and the +12v output terminal of the detector power conversion circuit. The specific circuit connection As shown in Figures 6, 7, and 8.

The band-pass amplifier circuit outputs the infrared flame amplitude signal and the infrared frequency signal to the detector data main processing circuit; the detector external signal input detection and self-inspection infrared LED drive circuit detects the external self-inspection signal and outputs it to the detector data main processing circuit , while receiving the infrared self-test driving signal of the system board to drive the self-test infrared LED drive circuit, the detector two-color LED drive circuit, and receiving the two-color LED control signal on the system board to drive the two-color LED drive circuit. The ultraviolet driving and signal sampling circuit outputs the driving signal of the step-up transformer through an independent processor, receives the adjustment signal of the main processing circuit of the detector data and outputs different driving signals according to the signal; the ultraviolet signal extraction and conversion circuit is processed by voltage conversion Drive the ultraviolet photoelectric tube, and obtain the ultraviolet flame signal through signal extraction and conversion and output it to the main processing circuit of the detector data; the self-test driving circuit of the ultraviolet sensor receives the self-test control signal of the main processing circuit of the detector data, and drives the ultraviolet light-emitting tube; The main processing circuit of the device data collects infrared radiation signal, infrared frequency signal, ultraviolet data and other input signals, and performs data processing. Detector power supply polarity conversion circuit and power supply anti-interference circuit provide non-polar DC power interface; the controller 4-20mA signal output circuit receives the PWM signal output by the detector data main processing circuit and converts it into a standard 4-20MA output circuit; the detector relay output circuit, the main processing circuit receiving the detector data outputs different drive signals, and outputs corresponding relay signals.

Infrared sensor, infrared light-emitting tube, band-pass amplifier circuit, detector external signal input detection and self-inspection infrared LED drive circuit and detector two-color LED drive circuit are fixed on the infrared detection board; ultraviolet drive and signal sampling circuit, data main processing circuit , the detector power conversion circuit, the ultraviolet signal extraction circuit and the ultraviolet sensor self-test drive circuit are fixed on the system and the ultraviolet detection board; the detector power polarity conversion circuit and the power anti-interference circuit, the detector isolation power supply 485 communication circuit, the detection Both the detector 4-20mA signal output circuit and the detector relay output circuit are on the detector signal output interface board. The signal transmission between the infrared detection board and the system and ultraviolet detection board is connected by pins, and the boards are fixed on the front panel by bolts. The signal transmission of the system and ultraviolet detection board and the signal output interface board is connected by flexible wires. The detector signal output interface The board is fixed to the back cover part of the detector. The detector is wired through the detector signal output interface board fixed on the back cover, and connected to the control system through the flameproof interface.

The UV sensor self-test drive circuit drives the self-test UV light-emitting tube to emit ultraviolet light, which passes through the UV protective lens and hits the reflector after reflection, and then enters the UV sensor through the UV protective lens again, and compares the preset UV luminescence by collecting the current detection value Control the modulation frequency and the initial detection parameters of the sensor to judge whether the sensor is in a normal working state, and infer whether the ultraviolet protective lens needs to be cleaned or replaced according to the frequency change range of the detection signal; at the same time, the detector external signal input detection and self-inspection infrared LED The driving circuit drives the self-test infrared LED to emit infrared light, which passes through the infrared protective lens and hits the reflector after reflection, and then enters the infrared sensor through the infrared protective lens again, and compares the preset infrared LED modulation frequency and sensor’s modulation frequency by collecting the current detection value. The initial detection parameters determine whether the sensor is in normal working condition, and can infer whether the infrared protective lens needs to be cleaned or replaced according to the change range of the detection value.

Detector self-inspection process: through the internal timer, when the accumulated time reaches the preset time, the detector detects whether there is a flame signal in the signal of the ultraviolet sensor. If there is no flame signal, it starts the ultraviolet light-emitting tube and detects whether the ultraviolet sensor is normal. Enter the detection infrared sensor, if it is abnormal, it will report the failure of the ultraviolet detector; at the same time, the detector will detect whether there is a flame signal in the signal of the infrared sensor, if there is no flame signal, start the infrared light-emitting tube, and check whether the infrared sensor is normal, if it is normal, enter the fire alarm judgment process, If it is abnormal, it will report the infrared detector failure.

1. Use the alarm shown in Figure 1, implement the detection according to the process shown in Figure 4, and perform infrared detection according to the following steps:

Step 1 Set the original data, which is initialized when the detector is powered on, namely:

Assuming that the infrared response is fixed at Cb, the flame channel’s fixed base value is Ca, the flame channel’s compensation base value is Ca ₁ , the current infrared AD sampling amplitude of the flame channel is A ₁ , and the infrared amplitude of the flame channel is increased by △ relative to the fixed base value A ₀ ＝A ₁ -Cb, the increase value of the infrared amplitude of the flame channel relative to the compensation base value △A ₁ ＝A ₁ -Cb, the infrared sampling frequency data of the flame channel are Fa ₀ (current), Fa ₁ , Fa ₂ , Fa ₃ (First 3 times) The average value of the current 4 infrared frequency data of the flame channel is Fap, N is a natural number, and the data size is set according to the signal ratio of the sensor.

Step 2 Judging based on the fixed base value, the workflow is shown in Figure 5

When A _i -Ca>Cb, if this condition is satisfied for 4 consecutive times, it is directly judged that the infrared amplitude meets the fire alarm condition. And skip the judgment procedure based on the compensation base value and judge the flicker frequency; when A _i -Ca<Cb, directly judge based on the compensation base value.

Step 3 Judging based on the compensation base value

When Al-Ca ₁ >Cb and this condition is met for 4 consecutive times, it is directly judged that the infrared amplitude meets the fire alarm condition.

Step 4 Judging the flickering frequency

4≤Fap≤20, and at least 2 of Fa ₀ (current), Fa ₁ , Fa ₂ , Fa ₃ (previous 3 times) satisfy 4≤Fa(i)≤20i=0, 1, 2, 3, then judge Satisfy the frequency to meet the fire alarm condition. Otherwise, the fire alarm condition is not met.

2. As shown in Figure 4, carry out UV judgment according to the following steps:

Step 1 Set the original data, which is initialized when the detector is powered on, namely:

Assume that the fixed high value of the UV response is X ₀ , the fixed low value of the flame channel is Y ₀ , the high value of the current UV frequency sampling of the flame channel is Z ₁ , and the low value of the current UV frequency sampling of the flame channel is K ₁ ,

Step 2 UV flame judgment program

When Z ₁ -X ₀ >0, and this condition is met for 4 consecutive times, it is directly judged that the high UV value meets the fire alarm condition, and the next judgment is made; when K ₁ -Y ₀ >0, and this condition is met for 4 consecutive times, it is directly judged that the ultraviolet Low value satisfies fire alarm conditions, otherwise no alarm will be given.

3. Ultraviolet and infrared composite judgment

When the infrared matches the fire alarm, the infrared fire alarm signal is output; when the ultraviolet light matches the fire alarm, the ultraviolet fire alarm signal is output; when one of the two signals matches the fire alarm signal, and the other is in the fire alarm warning state, it is paired according to the preset comparison parameters , if it meets the alarm state, it will report a fire alarm.

4. Signal output

The alarm signal is output through the detector 4-20mA signal output circuit or the detector relay output circuit. If it is an alarm signal, the operation ends. If it is not an alarm signal, it enters the detector self-test.

Claims (10)

1. a ultra-violet and infrared composite flame detecting alarm that has optical self-checking function comprises the ultraviolet protection eyeglass, infrared protection eyeglass, the logical amplifying circuit of band, detector data master treatment circuit, intelligence UV driven and signal sample circuit, the detector power-switching circuit, detector relay output circuit, detector 4-20mA signal output apparatus, ultraviolet is extracted and change-over circuit, the ultra-violet light-emitting pipe, the infraluminescence pipe, the ultraviolet photoelectric detection pipe, detector insulating power supply 485 communicating circuits, outer reflector, the input of detector external signal detects and self check infrared LED driving circuit and structure stationary installation; It is characterized in that behind ultraviolet protection eyeglass and infrared protection eyeglass, reflector being installed; The infraluminescence pipe links to each other with the logical amplifying circuit of band; The ultra-violet light-emitting pipe links to each other with intelligent UV driven and signal sample circuit with the ultraviolet photoelectric detection pipe; Connect a ultraviolet at detector power-switching circuit output terminal and extract and change-over circuit, at the output terminal connection detector data master treatment circuit of intelligent UV driven and signal sample circuit; The logical amplifying circuit of output terminal connecting band at detector external signal input detection and self check infrared LED driving circuit and detector data master treatment circuit; Output terminal at detector data master treatment circuit and detector power-switching circuit is connected detector insulating power supply 485 communicating circuits, detector 4-20mA signal output apparatus and detector relay output circuit.

2. a kind of ultra-violet and infrared composite flame detecting alarm that has optical self-checking function according to claim 1 is characterized in that described intelligent UV driven and signal sample circuit, adopts 8 single-chip microcomputers to carry out independent pulsed drive.

3. a kind of ultra-violet and infrared composite flame detecting alarm that has optical self-checking function according to claim 1, it is characterized in that ultra-violet light-emitting pipe and infraluminescence pipe and reflector form complete optics self checking structure, finish the self-checking function of detector by the driving of detector external signal input detection and self check infrared LED driving circuit and Ultraviolet sensor self check driving circuit.

4. a kind of ultra-violet and infrared composite flame detecting alarm that has optical self-checking function according to claim 1 is characterized in that described ultraviolet photoelectric detection pipe and ultra-violet light-emitting pipe adopt the step-up transformer power supply.

5. a kind of ultra-violet and infrared composite flame detecting alarm that has optical self-checking function according to claim 1 is characterized in that the logical amplifying circuit of described band adopts the digital zooming technology; Dynamic threshold technology is partly adopted in infrared extraction in the logical amplifying circuit of described ultraviolet extraction and change-over circuit and band; Detector is with logical the amplification at infrared sensor, and carries out the gain amplifier adjustment by digital regulation resistance.

6. a kind of ultra-violet and infrared composite flame detecting alarm that has optical self-checking function according to claim 1 is characterized in that described detector relay output circuit adopts the output of passive relay signal; Described detector 4-20mA signal output apparatus is by the pulse-width signal output of single-chip microcomputer.

7. a kind of ultra-violet and infrared composite flame detecting alarm that has optical self-checking function according to claim 1 is characterized in that the undesired signal on signal wire when described detector insulating power supply 485 communicating circuits adopt optocoupler, power isolation module, 485 communication chips and 3 moments to suppress diode inhibition external communication.

8. the method that adopts the described ultra-violet and infrared composite flame detecting alarm that has optical self-checking function of claim 1 to survey, it is characterized in that adopting infrared detection and the parallel mixing detection mode of ultraviolet detection, by ultraviolet and infrared compound judgement fire alarm, carry out according to the following steps:

The step 1 system initialization

System reset is closed and is interrupted, relay, port, RAM and timer T0, T1 initialization, and gathering reports to the police is provided with and the sensitivity setting, lighted red LED 5 seconds, green LED 5 seconds, AD initialization, timer T2 initialization, set and open interruption, clear house dog zone bit, circular wait is interrupted;

The step 2 signals collecting realizes by coding

Carry out AD after regularly interrupting by T2 and be converted to, obtained the signal amplitude and the frequency data of two passages, judge by interrupting, carry out corresponding interrupt operation, enter T2 regularly behind the interrupt service subroutine sequence of operation be: T2 regularly interrupts initialization; Fire alarm is judged; Whether need frequency collection; Whether need the amplitude sampled data; Whether needing to carry out fire alarm comprehensively judges; T2 regularly interrupts returning then;

The step 3 signal Processing

The data of gather are carried out algorithm bring computing into, judged whether that by algorithm fire takes place, specific algorithm is 4 parts: (1) infra red flame amplitude judges that (2) infra red flame frequency is judged, (3) the ultraviolet flame frequency signal is judged, the infrared compound judgement of (4) ultraviolet;

The output of step 4 signal

By detector 4-20mA signal output apparatus or detector relay output circuit alerting signal being exported, is then end of run of alerting signal, is not that alerting signal then enters the detector self check.

9. the method that the ultra-violet and infrared composite flame detecting alarm that has optical self-checking function according to claim 8 is surveyed is characterized in that described its specific algorithm of step 3 signal Processing carries out according to the following steps:

(1), the infra red flame amplitude is judged

1. based on fixedly base value judgement

Work as A _i-Ca 〉=Cb and (A _i-Ca)/and n 〉=Cb, wherein n is a natural number, A _iBe the current infrared AD sample magnitude of passage of flame, be the fixing base value of passage of flame, Cb is the infrared response fixed value, is the ratio that the signal amplitude of passage increases; In the judgement number of times of setting, satisfy this condition and judge that then amplitude satisfies the fire alarm condition, skip based on the compensation base value determining program line flicker frequency of going forward side by side and judge; Work as A _i-Ca＜Cb then carries out judging based on the compensation base value;

2. judge based on the compensation base value

Work as A _i-Ca ₁〉=Cb ₁And (A _i-Ca ₁)/n 〉=Cb ₁, in the judgement number of times of setting, satisfy this condition and judge that then amplitude satisfies the fire alarm condition, carry out flicker frequency and judge;

(2), the infra red flame frequency is judged

Infra red flame passage frequency data mean value in the judgement number of times of setting is Fav, 4≤Fav≤20, and the infrared sample frequency data of passage of flame be followed successively by Fa0 (current), Fa1, Fa2 ..., Fa _i(i=N), wherein continuous 4 secondary frequencies satisfy 4≤Fa _i≤ 20 (i=N),, then the fire alarm condition is satisfied in the flicker frequency judgement;

(3), the ultraviolet flame frequency signal is judged

Ultraviolet flame passage frequency data mean value in the judgement number of times of setting is Fuv, Fmin≤Fuv≤Fmax, and ultraviolet flame channel frequence data Fu0 (current), Fu1, Fu2 ... Fu _i(i=N), wherein continuous 4 secondary frequencies satisfy Fmin≤Fa _i≤ Fmax (i=N), then the fire alarm condition is satisfied in the judgement of ultraviolet flicker frequency;

(4), the infrared compound judgement of ultraviolet

When meeting fire alarm, export infrared fire alarm, when infrared when ultraviolet meets fire alarm, output ultraviolet fire alarm, when two kinds of signals have a kind of when meeting fire alarm, when another kind is in the fire alarm alert status, match according to the reduced parameter that sets in advance, then report a fire if meet alarm condition.

10. the method that the ultra-violet and infrared composite flame detecting alarm that has an optical self-checking function according to claim 8 is surveyed is characterized in that described step 4 signal exports its detector self check workflow and be:

Pass through timer internal, cumulative time reaches when preestablishing the time, detector detects the Ultraviolet sensor signal and whether has flare up fire, if no flare up fire then starts the ultra-violet light-emitting pipe, whether and it is normal to detect Ultraviolet sensor, normally then enter the detection infrared sensor, the undesired ultraviolet detector fault of promptly reporting; Whether the infrared sensor of detector detection simultaneously signal exists flare up fire, and whether if no flare up fire then starts the infraluminescence pipe, and it is normal to detect infrared sensor, normally then enters fire alarm and judges flow process, the undesired infrared eye fault of promptly reporting.

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