Vertical two-way dispersion smoke sensing detector labyrinth

Abstract

The labyrinth includes probing chamber composed of labyrinth cover and labyrinth base, as well as forward scattering light path and back scattering light path constituted from transmitting tube (3), transmitting tube (6) and receiving tube. Dual scattering light paths including two transmitting paths and one receiving path are adopted in the invention. Using characteristics of different responses on particles in different colors from forward or back scatterings, the method recognizes smog in different colors and grain sizes in order to distinguish not fire alarm factors such as water spray, dust etc so as to raise responsibility of detector, and lower rate of false alarm. Comparing prior art, the invention possesses advantages of superior orientation responsibility, reasonable design, balanced responses for smog in different colors and grain sizes, and lower cost. The invention is applicable to spot type optical detector of fire smoke in auto fire alarm system.

Description

Technical field: [0001] The utility model relates to the technical field of automatic fire alarm, in particular to a labyrinth component used for a point-type photoelectric smoke fire detector. Background technique: [0002] There are two types of smoke detectors widely used in automatic fire alarm systems: ionization smoke detectors and photoelectric smoke detectors. Although the ionization smoke detector has a balanced response to smoke of various colors, it contains a low-energy alpha radiation source, which cannot meet the requirements for environmental protection of products, and has basically been replaced by photoelectric smoke detectors. [0003] At present, the photoelectric smoke detector generally adopts a vertical or horizontal forward scattering maze. The infrared light emitting tube and the receiving tube form a forward scattering optical path with an optical axis angle greater than 90°. The light is absorbed by the side wall of the maze, and the receiving tub...

AI Technical Summary

Problems solved by technology

However, the transmitting tube and the receiving tube form a large entity close to the outer wall of the maze, which affects the azimuth response performance of the detector; in addition, the static background value caused by lengthening the optical path and reducing the direct reflection of infrared light is too large, and the radial size of the maze is large. In addition, lenses are often used in front of the transmitting tube and receiving tube, resulting in larger detector volume, increased cost, and inconvenience in production. At the same time, the response range to smoke is reduced and it is sensitive to the accumulation of dust.

[0006] The vertical two-way scattering maze that has been proposed so far adopts the method of sending out and receiving twice, that is, one transmitting tube and two receiving tubes. Entity, which affects the azimuth response performance of the detector; in addition, it is necessary to install a lens and a set of receiving amplifier circuit, which also increases the production cost and complicates the production assembly

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