| 摘要 |
1321016 Smoke and dust detector EUROPEAN ATOMIC ENERGY COMMUNITY (EURATOM) 19 April 1971 [9 Feb 1970] 20898/71 Heading G1A In an apparatus for detecting smoke or dust particles in a gas, the gas is passed along a meandering path which crosses and recrosses a light beam travelling in a straight line from a source to a detector. In an embodiment comprising a light source 8 and a detector 9 at either end of an elongated duct 4 the meandering gas path is formed by a number of baffles 7 which have semicircular cut outs or slots, for the light beam and are arranged as shown. When the detectors output drops to below a predetermined but adjustable value an alarm is activated. The gas is sucked into the duct 4 via inlet 6 by means of a blower 2 and leaves via outlet 5. The light source may be monitored by means of a light guide 10 which by-passes the duct 4 to enable any variation in source output to be corrected automatically. |
