| 摘要 |
1,246,355. Fire fighting with foam. H. C. STULTS. 19 Aug., 1969 [9 Dec., 1968], No. 41424/69. Heading ASA. [Also in Division B1] A fire extinguishing system comprises a tank 24 containing a foam-forming solution and a foam generator comprising a perforated screen 56, nozzles 60 through which foamforming solution from tank 24 is sprayed on the screen, and a duct formed in part by walls 52, 54 through which air is induced when the foam-forming solution issues from the nozzles. The screen may be inclined as shown to direct the flow of foam downwards and may be coated with a rough-surfaced paint to assist foam generation. The foam-forming solution may be supplied to the nozzles on detection of a fire by sensor 26, a signal from the sensor causing valve 34 to be actuated to permit gas under pressure in cylinder 22 to enter tank 24 and force the solution therein to the nozzles. The foamforming solution may be an aqueous surfactant solution prepared from a concentrate comprising an ammonium salt of a sulphated primary alcohol ethoxylate containing an average 3 ethylene oxide units, C 12-15 primary alcohols, ethanol, and the mono butyl ether of ethylene glycol. |
