Continuously variable controlled orifice inflator

摘要

Vehicle airbag inflator including a container (12) accommodating a source of gas and a cylindrical diffuser (16) inside which a piston (60) with a conical radially extending surface (62) is slidable against the force of a compression coil spring (70). When pressure within the container rises above a threshold value a burst disc (22) ruptures permitting gas to pass into an opening (24) and flow over the conical surface (62) of the piston (60) causing the piston to uncover gas outlet openings (40) in the diffuser (16). A piston guide pin (54) connected to a guide base (52) engages a cylindrical through bore (68) in the piston (60). The gas source may include a store of pressurised gas, combustible gas generating material or a combination of both. The inflator can be designed to provide a customised, non-linear control of the flow of gas from the inflator.