GB1464613A - Inflator - Google Patents

Abstract

1464613 Generating combustion products under pressure GENERAL MOTORS CORP 6 June 1974 [25 June 1973 (2) ] 25139/74 Heading F1L [ Also in Division F2] A combustion gas generator for inflation of a restraint cushion in a vehicle comprises a cylindrical pressure vessel 12 containing a fluid, e.g. argon, and a cartridge assembly 60 removably retained in a cylindrical casing 36 closed at one end by a rupturable wall 42. Cartridge assembly 60 comprises a plastics housing 62 containing a hollow cylindrical propellant 72 and at one end a metal plate 74 having a fluted outlet orifice 76. The other end of housing 62 is closed by an integral wall 66 having cylindrical bores 68, 70 containing respectively electrically fired squibs 78, 80. A metal ball 82 is also retained within bore 70. An igniter plug 90 electrically connected to squibs 78, 80 is carried by a seal plate 86 secured to wall 66, plate 86 having a chamfered edge 88. The latter is engaged by a circlip 92 which retains cartridge assembly 60 within casing 36 against the action of a biasing spring 96. When an impact sensor fires squibs 78, 80, the former ignites propellant 72 and the latter fires ball 82 into orifice 76 to restrict the flow area thereof and thus increase the burn rate. At a predetermined pressure, wall 42 ruptures causing a rod 50 to move rightwards within sleeve 54 rupturing the pressure vessel outlet 20. A mixture of combustion gases and argon thus flows through holes 28 in outlet member 22 and thence via manifold 32 and diffuser' 34 to inflate the restraint cushion. Casing 36 is designed to fail at groove 98 if the combustion pressure becomes excessive. An argon filling and bleed valve assembly, (136), Figs. 3, 4 (not shown) may be provided (see Division F2).