Vehicle safety system pyrotechnic actuator, especially for raising engine hood on impact with pedestrian, includes piston-cylinder assembly, membrane and gas generator

摘要

A piston (1) is mounted on a casing (2). A resilient membrane (3) separates the casing into two parts. The first part (21) is a reservoir, and includes both the piston and a fluid (25). The second part (22) contains the gas generator (4). The piston slides in a cylinder (5) which is connected with the casing. The piston comprises a telescopic stack of at least two cylinders, fixed to the casing. A rod is mounted on the piston. The second part of the casing includes a vent orifice (24). The fluid is a water-based mixture. The casing is cylindrical, formed by two shell halves (26, 27), the membrane (3) being mounted between their edges (29). The gas generator includes a support (41) and a central channel (43). The first end of the channel discharges into the second part (22) of the casing, and a gas generator (4) is mounted at the other end of the central channel. An independent claim is included for a corresponding pedestrian protection system, based on raising the bonnet (or hood) of the vehicle upon impact.