SU1241272A1 - Fume detector - Google Patents

Abstract

This invention relates to the field of automatic fire alarm. The aim of the invention is to improve the functional reliability of the device by monitoring the integrity of the fiber. The smoke sensor comprises a light guide 1, which is directed by an input end to the radiation source 4. The light guide is located around the protected (L

Description

spaces and has gaps 2 at controlled points, focusing elements 3. At each break 2 light guide 1, radiation collectors 5 are installed, the number of which corresponds to the number of breaks in the light guide 1. The collectors 5 are made in the form of opaque cylinders 6, on the inner surface of each of them laid; zigzag-shaped along the generatrix and fixed non-interlaced (continuous optical fiber 7 coated with a transparent cladding 7. Each collector 5 is located coaxially with the light-guide 1 in the place of its rupture. Both ends are optically The common fiber 7 of each collector 5 is connected to the inputs of the optically coupled cable 8 corresponding to the collector, output

The invention relates to an automatic fire alarm system, in particular to smoke detectors using fiber optics, which are built on the principle of recording scattered smoke of light.

The purpose of the invention is to increase the functional reliability of the device.

The drawing shows a block diagram of a smoke detector,

The smoke sensor contains a light guide 1 with discontinuities 2 at the controlled points 15 of each section of the light guide, the radiation focusing element 3 is installed, sent by the radiation source 4. At the points where the fiber 1 breaks, he has coaxially installed collectors 5, made in the form of opaque cylinders 6, on the inner surface of which optical fiber 7 (unprotected or covered with a transparent sheath) is laid zigzag along the forming surface. Both ends of the optical fiber 7 of each collector are connected to an optical directional coupler 8 corresponding to this collector. Outputs of all response 8 of the collectors 8 are connected to the inputs of the corresponding photodetectors 9. Output

which is connected to the input of the corresponding photodetector 9. The output of each photodetector 9 is connected to the first input of the corresponding summer 10. The outputs of all adders are connected to the inputs of multiplexer 11, the output of which is connected to the input of the display unit 12. The output end of the optical fiber 1 is connected to the input of the control photoreceiver 16 , the output of which is connected through the amplifier 17 to the second inputs of all adders - and to the input of the indicator 18. At the break of the light guide 1 there is information on the indicator 18, and on the display unit 12 is missing. In the case of serviceability of the light guide 1, information on the place of the appearance of smoke is displayed on the display unit 12. 1 sludge.

each photodetector 9 is connected to the input of the corresponding adder 10. The outputs of all adders 10 are connected to the inputs of multiplexer 11, the output of which is connected to the input of the display unit 12 containing the counter 13, the decoder 14 and the indicator 15, the output of which is informative. The output end of the optical fiber 1 is connected to the input of the control photodetector 16, the output of which through amplifier 17 is connected with the indicator 18 of the optical fiber 1, containing, for example, the amplifier 19 and the display element 20, on which signals about the break of the optical fiber 1 are displayed.

The smoke detector works as follows.

The light from the radiation source 4 enters the input of the light guide 1 (its first section). The focusing elements 3 of each section of the light guide 1 direct the flow of light to the next section. The light from the output end of the last section of the light guide 1 is sensed by the control photodetector 16, then amplified by the amplifier 17 and fed to the second inputs of all the TO, as well as to the input of the indicator 18. If

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the light guide 1 is intact and has bursts only at the set break points 2, the signal from the output of the control photodetector 16 is sensed by the indicator 18. In case of a break of the light guide 1, the radiation of the source 4 does not come to the input of the control photoreceiver 1, and therefore the signal does not go to the input of the indicator 18 (cliff).

In the case of smoke appearing at any of the control points (with a whole light-1), smoke also appears in the corresponding gap 2 of the fiber. The light passing through this gap 2 is reflected in different directions from the smoke particles and is perceived by the zigzags of the optical fiber 7, laid on the inner surface of the cylinder 6. The reflected light is perceived immediately by the large area of the optical fiber 7, which is densely packed in a small area,. it goes both ways and enters the inputs of the optically directed response ate 8. From the output of the coupler 8, the light enters the input of the photodetector 9 corresponding to this controlled point 9. The electrical signal generated by the photodetector ISRC 9 is supplied to a first input of the adder 10 sootvetstvuk Oleg Zhegoyev.

In the absence of smoke in the gap 2 of the light guide 1 to the first input of the adder 10, the signal is not received.

If two signals are simultaneously present at the inputs of the adder 10 (optical fiber operability and the presence of smoke at the test point), a signal also appears at its output, which is fed to the input of the multiplexer 11 corresponding to this point. If at the input of the adder 10 there is only signal of the fiber integrity, there is no signal at its output. There will be no signal at its output and in the presence of only a signal about the presence of smoke, however, in this case the indicator 18 is triggered and gives information about the presence of a break in the light guide 1,

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Order 3603/46. Circulation 515.

Random polygons pr-tie, Uzhgorod, st. Project, 4

2724

The multiplexer 11 senses signals from adders 10 arriving at its inputs and sends to the input of display unit 12 information about the specific points of the controlled space that have a fire situation, which is fixed by indicator 15.

Claims (1)

Invention Formula A smoke sensor containing a radiation source, an p-sectional light guide facing the radiation source, located around the protected space and having section mappings at controlled points, radiation focusing elements installed in the fiber section and an indicator that , with the aim of increasing the reliability of the sensor; a multiplexer, a control photodetector, an indication unit, and p-1 photodetectors, adders, optically directional couplers, radiation collectors, and radiation collectors are impressed in the form of opaque lines; an unprotected. or a continuous optical fiber covered with a transparent sheath is fixed, each radiation collector is located coaxially to the light guide at the interface, both ends of the optical Each collector's fiber is connected to the inputs of the optical directional coupler corresponding to this collector, which is connected to the input of the corresponding photodetector, the output of each photoreceiver is connected to the first input of the corresponding adder, and the outputs of all adders fiber is connected to the input of the control photodetector, the output of which is connected to the second inputs of all north-west maters and to the input of indi Ator Subscription