GB1332009A - Containers discharged by gas under pressure - Google Patents

Abstract

1332009 Powder fire extinguishers CHUBB FIRE SECURITY Ltd 18 April 1972 [5 May 1971] 13312/71 Heading A5A In fire-extinguishing apparatus comprising a container 16 of extinguishant discharged by a separate source of pressurised gas 15, the gas flow into 16 is controlled by a valve responsive to the container presure, and compensating means make the valve action independent of the incoming gas pressure. The valve is threaded into the top of 16 and has inlet port 11 connected to gas bottle 15 and outlet port 12 leading to ports 17 in the powdered extinguishant; the latter is thereby discharged through pipe 18. The valve comprises socket 1 in which is mounted housing 3 for closure member 4 on stem 5. The foot of 5 is threaded into piston 6 slidable in cavity 7 which is vented at 8 to atmosphere. Spring 9 surrounding stem 5 bears on piston 6 urging valve closure member 4 downwards and off valve seat 10, to open up a passage between inlet 11 and outlet 12. The spring action is countered by container pressure on the underside of piston 6, and is overcome when the latter pressure reaches a predetermined value. The valve then closes. Stem 13 extending upwards from 4 carries piston 14 of the same diameter as seat 10. Thus when the valve is open there is equal pressure on piston 14 and member 4 and operation of the valve depends solely on container pressure. The arrangement enables a true gas, e.g. compressed N 2 , to be used. CO 2 can also be used.