GB1388697A - Pyrotechnic generator of gas under pressure - Google Patents

Abstract

1388697 Generating combustion products under pressure SOC NATIONALE DES POUDRES ET EXPLOSIFS 31 Oct 1972 [ 8 Nov 1971] 50138/72 Heading F1L A combustion gas generator comprises a cylindrical casing divided by a transverse partition 26 into a combustion chamber 6 containing a solid propellant and a second chamber 9 containing a solid coolant 29, there being means to direct the combustion gases into chamber 9 and prevent them from flowing directly there-through. The generator may be used for inflating lifeboats or sledges or for fire extinguishing. In the arrangement shown partition 26 has peripheral gas flow ports 27 and direct flow through coolant chamber 9 is prevented by a helical screw 28. The cooled gases leave chamber 9 through a filter grid and outlet nozzle 4. In a modification, Fig.3 (not shown), the helical screw (22) tapers towards the outlet nozzle and ports 26 are replaced by two oblique orifices (24) directed in the same sense as the helix and covered by diaphragms (17) which rupture at the moment of ignition. In another arrangement, Fig.6 (not shown), the dividing partition (30) has a central nozzle 31 which directs the combustion gases into a chamber (32) containing a deflector (33) integral with a grid (34) which retains the coolant, the grid being divided into compartments by a bundle of metal tubes (35). The coolant consists of granules of hydrated or anhydrous salts which can be decomposed by heat, e.g. ammonium carbonate, bicarbonate, carbamate, chloride, acetate or oxalate, calcium oxalate, guanidine oxalate or nitrate, aminoguanidine nitrate, or urea. The solid propellant may be slow burning having a potential of 483 cal/gm.