Pyrotechnic gas generator for inflatable air-bag of a motor vehicle

摘要

The invention relates to a pyrotechnic gas generator (1) intended for motor vehicle safety. The generator (1) comprises a hollow cylindrical body (2, 3) having gas outlet orifices (4) and being closed by a ring (6). The generator (1) contains an annular pyrotechnic charge (18) arranged around an ignition device (14, 16, 17) carried by the closure ring (6). The charge (18) essentially consists of a silicone binder and a mixture of ammonium perchlorate and of sodium nitrate. Its dimensions are less than the internal dimensions of the body of the generator, so that the ratio (dead volume/volume of the block) lies between 2 and 1 in order for it to be possible for the gases originating from the ignition device (14, 16, 17) to cover all of the free surfaces of the charge (18). A thin metal casing (25) is interposed between the charge (18) and the orifices (4). The generator is used for inflating an air bag.