RU2340947C2 - Fire fighting smoke optic-electronic detector - Google Patents

Abstract

FIELD: fire equipment.

SUBSTANCE: invention concerns devices of the fire alarm system, namely: to a design of fire-fighting smoke optic-electronic detectors. The device contains the case having demountable connection with the basis, where the electric contacts are fixed, and also the printed-circuit board with elements of the electronic scheme placed in the case and the optical camera containing a light source and a photo detector, thus the printed-circuit board is located between the case and the optical camera. The case can be supplied by the springs fixed in it by the central part and resting by one end in the printed-circuit board, and other end - in electric contacts of the basis.

EFFECT: decrease of production and maintenance cost, materials-output ratio, simplification of assemblage, service and repair.

2 cl, 1 dwg

Description

The invention relates to a fire alarm device, namely, to the design of fire smoke optoelectronic detectors.

Known fire optoelectronic detectors contain a housing fixed to the base with an optical camera that prevents the penetration of extraneous light into it and is accessible for air with smoke. Inside the camera there is a light source and a photodetector protected from it by an opaque screen. When smoke particles penetrate into the chamber, the light of the source is scattered on them, and part of this scattered light enters the photodetector, generating an electrical signal.

Known from the patent DE 4412212, a fire smoke optical electronic detector comprises a measuring optical camera in the form of a flat cylindrical box, which is fixed with one end side to a plate connected to the ceiling of the controlled room, and its side wall is formed by a mesh for protection against insects. The end wall of the measuring chamber, remote from the named plate and facing the dome of the detector, is closed with a flat bottom.

Documents (international application РТС / СН 97/00270; US 5400014; US 5430307; DE 3334545; Product catalog IVS - Signal-special automation, Obninsk, 2002, page 5 "Optical-electronic smoke smoke detector IP 212-44 (DIP -44) open a fire smoke optoelectronic detector containing a housing having a detachable connection to the base, an optical camera placed in the housing and attached to it from the side facing the base, a printed circuit board with electronic circuit elements.

Such a traditional arrangement of the detector structural elements leads to its cost increase, as it complicates its layout, increases the printed circuit board area, requires the installation of an additional protective cover that covers the case with the circuit board and optical camera, and makes it difficult to assemble and disassemble the detector.

Currently, designers in all known developed optoelectronic detectors have a measuring optical camera between the detector housing and the printed circuit board with electronic circuit elements.

Moreover, in known designs, the location of the printed circuit board near the base made it advisable to make an electrical connection of the printed circuit board with the contact elements of the housing intended for jointing with the contacts of the base, either by soldering or using threaded connections.

Within the framework of this application, the task of developing such a detector design that would ensure a reduction in the cost of a fire optoelectronic detector and operating costs by reducing the number of detector parts, reducing the material consumption of parts, simplifying its assembly, maintenance and repair is solved.

This goal is achieved by the fact that in a fire smoke optoelectronic detector containing a housing having a detachable connection to a base on which electrical contacts are fixed, as well as a printed circuit board with electronic circuit elements and an optical camera containing a light source and a photodetector, a circuit board is located between the case and the optical camera.

The preferred design of the detector, in which the housing is equipped with springs fixed in it with its central part and abutting one end against a printed circuit board, and the other end into the contacts of the base.

With such a detector design, there is no need to use a housing cover to protect a printed circuit board with electronic circuit elements, since its role is played by an optical camera, all structural elements can be made more compact, and the assembly and disassembly of the detector is simplified.

The essence of this fire optoelectronic detector is illustrated by the drawing, which shows a vertical section of a fire detector with diffused light.

The detector shown in the drawing consists of a base 1 with contacts 2, a housing 3, an optical camera 4 with a light source 5 and a photodetector 6 located inside it, separated by an opaque partition 7, a printed circuit board 8 with electronic circuit elements. To simplify the assembly and disassembly of the detector, the electrical connection of the printed circuit board 8 with the contacts 2 of the base 1 is provided using clamping springs 9, abutting against the printed circuit board 8 at one end, and when connecting the detector housing 3 with the base 1, they make electrical contact with the contacts 2 of the base 1. The central part of the springs 9 is made in the form of a saddle, which is installed (put on) on a specially made for this partition 10 of the housing 3.

This optical-electronic fire detector works as follows. A light source 5 based on an infrared LED emits light pulses into the space of the optical camera 4 and in standby mode does not fall on the photodetector 6. When smoke enters the optical camera 4, the light of the source is scattered on it, and part of this scattered light enters the photodetector 6. Generated by the photodetector the electrical signal is amplified and processed by the elements of the electronic circuit of the printed circuit board 8.

The design of the detector according to the invention with a printed circuit board 8, located between the housing 3 and the optical camera 4, provides a commercial advantage of this fire smoke optical-electronic detector, which consists in reducing the cost of its manufacture and operation due to the simplification of its design and material consumption.

Claims (2)

1. Fire smoke optoelectronic detector comprising a housing having a detachable connection to a base on which electrical contacts are fixed, as well as a printed circuit board with electronic circuit elements and an optical camera containing a light source and a photodetector, characterized in that the printed the board is located between the case and the optical camera. 2. The device according to claim 1, characterized in that the housing is equipped with springs fixed in it with its central part and abutting one end against a printed circuit board, and the other end into electrical contacts of the base.