RU2459269C1 - Pyrometric fire hazard coordinate sensor with cylindrical lenses - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: pyrometric sensor has series-arranged optical system, light flux splitter, light filters with different transmission spectra, single-coordinate radiation detectors lying perpendicular to each other and the optical axis of the sensor. The pyrometric sensor further includes two cylindrical lenses, each in its own optical channel.

EFFECT: faster operation, which increases efficiency of the fire-extinguishing or explosion suppression system.

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Description

The invention is intended to detect a source of ignition in gas dispersed media and to determine its two-dimensional coordinates by thermal radiation.

The invention relates to the field of hazard warning systems, in particular to fire alarm and explosion suppression devices, and is intended to detect a source of ignition by radiation from a source of elevated temperature. The invention can be used in automatic fire alarm systems to ensure the explosion safety of gas dispersed systems (continuous phase gas) in a production environment and in coal mines.

A known pyrometric coordinate sensor of the ignition source [1, prototype], containing a sequentially mounted optical system, a light splitter, filters with different transmission spectra, single-axis radiation receivers (OPI) located perpendicular to each other and the optical axis of the sensor, the outputs of the receivers connected to the input executive scheme. The disadvantage of this sensor is that the image from a point emitter (ignition at the initial stage), offset from the center of the protected zone, does not fall (is not projected) onto one or both of the optical arrays, which can lead to a miss of the initial moment of ignition.

The proposed technical solution has all the advantages of a prototype (the spectral ratio method is implemented, the ability to determine the coordinates of a fire source), but, in turn, it has a higher reliability of detecting fires at an early stage due to the possibility of detecting fire centers shifted relative to the center of the protected area.

The essence of the technical solution consists in the use of two cylindrical lenses located after the luminous flux separator, each in its optical channel, so that the segment into which the luminous flux is focused by the lens intersects the corresponding single-axis radiation detector.

The principle of operation of the invention is illustrated using the scheme (figure 1). The device comprises an optical system 1, a luminous flux separator 2, cylindrical lenses 3, light filters 4 and 4 ', single-axis radiation receivers 5, an executive circuit 6, a power supply 7.

Pyrometric coordinates of the ignition source with cylindrical lenses works as follows.

The radiation of the controlled area is collected using the optical system 1 and is divided by a beam splitter plate 2 into two streams (optical channels). Each of these streams, by means of cylindrical lenses 3, is focused into the segment that intersects the OIE 5; at the same time, a narrow energy spectrum is released by filters 4 and 4 '. The signals from the optical arrester are fed into the executive circuit 6. The executive circuit converts the digital distribution of the magnitude of the electrical signals along the length of the horizontal and vertical optical arrays, performs software filtering of noise, determines the area of the sensitive layer with maximum illumination by the extremum of the electrical signal for each optical arrester, and, based on this calculates the two-dimensional coordinates of the source of ignition, calculates the ratio of the extrema of the electrical signals and compares the resulting ratio with a predetermined value for deciding on the occurrence (or absence) of a fire. In the event of a fire, the executive circuit generates a control signal to the corresponding explosion suppression device.

The power supply 7 serves to form and stabilize the voltages necessary for the operation of the electrical circuit.

The pyrometric sensor of coordinates of the ignition source with cylindrical lenses has successfully passed laboratory tests.

Currently, BTI AltGTU is actively cooperating with coal mines of the Kemerovo region in the field of development and implementation of fire detection sensors.

Information sources

1. RF patent No. 2318242.

Claims (1)

A pyrometric sensor of coordinates of the source of ignition, containing a sequentially installed optical system, a light splitter, filters with different transmission spectra, single-axis radiation receivers located perpendicular to each other and the optical axis of the sensor, the outputs of the receivers connected to the input of the actuating circuit, characterized in that it further comprises two cylindrical lenses located after the light flux separator, each in its own optical channel, and a segment in which focuses the light flux, crosses the corresponding single-axis radiation receiver.