RU2597466C1 - Fire source coordinate sensor - Google Patents

Abstract

FIELD: measuring equipment; fire safety.

SUBSTANCE: invention relates to fire alarm devices, and is intended for detection of fire source in gas-dispersion systems (solid phase-gas) and determining its two-dimensional coordinates at heat radiation source. Proposed sensor comprises serially mounted inlet spherical lens, light flux splitter, two cylindrical lenses, each in its optical channel, light filters with different transmission spectra, single-coordinate radiation detectors, located perpendicular to each other and the optical axis of the sensor also includes two pairs of mirrors, each pair is located after each cylindrical lens.

EFFECT: increased sensitivity, higher efficiency of fire-extinguishing or explosion suppression system.

1 cl, 1 dwg, 1 tbl

Description

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 in gas dispersed systems and determine its two-dimensional coordinates from radiation from a source of elevated temperature.

A known pyrometric sensor of coordinates of the source of ignition [1], containing a sequentially installed optical system, a light splitter, light 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 of the Executive circuit . The disadvantage of this sensor is that the projection 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.

Known pyrometric coordinates of the ignition source with cylindrical lenses [2, prototype], containing a sequentially mounted spherical lens, a light splitter, two cylindrical lenses located after the light flux splitter, each in its optical channel, filters with different transmission spectra, single-axis radiation receivers (OPI) located perpendicular to each other and the optical axis of the sensor. The axial lines of the OPI are oriented across the longitudinal axes of the cylindrical lenses. The outputs of the receivers are connected to the input of the Executive circuit. The disadvantage of this sensor is that most of the energy focused by the optical system passes by the OPI, which, in turn, leads to a low sensitivity of the sensor.

The task to which the proposed technical solution is directed is to develop a sensor of coordinates of the fire source with increased sensitivity, capable of detecting fires at an earlier stage.

The proposed sensor of the coordinates of the source of ignition contains an optical system containing a spherical lens sequentially mounted, a luminous flux separator, two cylindrical lenses located after the luminous flux separator, each in its optical channel, two filters with different transmission spectra, single-axis radiation receivers (OPI) located perpendicular to each other and the optical axis of the sensor, and two pairs of mirrors are additionally introduced. Each pair is installed after each cylindrical lens, which leads to the focusing of optical energy on the OPI. The angle β between the plane of the mirror and the optical axis (Fig. 1) determines the coefficient of sensitivity increase k, in comparison with the prototype (Table 1).

So, at β = 16 ° ± 1 ° this coefficient is 3.4 ± 0.1, i.e. sensor sensitivity increased 3.4 times. At other angles, the coefficient is lower. For β = 0 ° and β> 45 °, the coefficient is 1.

In FIG. 1 is a structural diagram of a coordinate sensor of a fire source. The device contains an input spherical lens 1, a light flux separator 2, cylindrical lenses 3 and 3 ′, pairs of mirrors 4 and 4 ′, light filters 5 and 5 ′, single-axis radiation receivers 6 and 6 ′, actuating circuit 7, power supply 8.

The coordinate sensor of the source of fire works as follows.

The radiation of the controlled region is collected using a spherical lens 1 and is divided by a beam splitter plate 2 into two streams (optical channels). Each of these flows is focused by means of cylindrical lenses 3 into a segment that intersects the OPI 6. A part of the energy that passes by the OPI is focused by two pairs of mirrors 4 and 4 ′ and reaches the receiver. At the same time, a narrow energy spectrum is extracted with the light filters 5. The signals from the OPI are fed into the executive circuit 7. The executive circuit 7, built on the basis of the microcontroller, converts into digital values the distribution of the magnitude of the electrical signals along the length of the horizontal and vertical OPI, performs software noise filtering, determines the sensitive area layer with maximum illumination at the extremum of the electrical signal for each IRF and based on this calculates the two-dimensional coordinates of the source of ignition After that, it finds 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 device for suppressing fire.

The power supply 8 is used to form and stabilize the voltages necessary for the operation of the electrical circuit.

Thus, the proposed technical solution is able to solve the problem - to significantly increase the sensitivity of the sensor.

The ignition source coordinate sensor has been tested in an installation for explosions of coal-methane-air mixtures at the Altai State Technical University. I.I. Polzunov, who confirmed the implementation of the claimed technical result.

The invention can be used in automatic fire alarm systems to ensure the explosion safety of gas dispersed systems (continuous phase gas) in production conditions and in coal mines, in particular mines of the Kemerovo region, where analogues of this sensor, made by a team of authors of the proposed technical solution, are already successfully used.

Information sources

1. RF patent No. 2318242.

2. RF patent No. 2459269.

3. RF patent No. 2109345.

4. US 5339070 A, 08.16.1994.

5. Yakushenkov Yu.G. Theory and calculation of optoelectronic devices: A textbook for students of instrument-making specialties of universities. - 3rd ed., Revised. and add. - M.: Mechanical Engineering, 1989. - 360 p.: Silt, p. 186-188.

Claims (1)

An ignition source coordinate sensor containing a sequentially installed input spherical lens, a light flux separator, two cylindrical lenses, each in its optical channel, two filters with different transmission spectra, two single-axis radiation receivers located perpendicular to each other and to the optical axis of the sensor, axial lines of single-axis radiation receivers are oriented across the longitudinal axis of the cylindrical lenses, and the outputs of the receivers are connected to the input of the Executive circuit, distinct In that it further comprises two pairs of mirrors, each pair of mirrors is located after each cylindrical lens.

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