Pyrotechnic hot-gas generator for side protection bag

Claim 1

Pyrotechnic hot-gas generator (1) comprising a hollow cylindrical body (2) which has a side wall (3) ending in two substantially planar faces (4, 5) and in which the length (L) of the generatrices is greater than its external diameter (D), the said body containing especially an igniter (8) and a gas-generating solid pyrotechnic charge (20), characterized in that: i) the said side wall (3) is solid over the whole length of each of its generatrices and each of the planar faces (4, 5) has an opening (6, 7), ii) the said igniter (8) is fixed in one of the said openings (6), iii) a nozzle (16, 19), itself closed by a closure cap (18), is fixed in the other opening (7), iv) the said pyrotechnic charge is in the form of a block perforated with a plurality of channels (24) which are parallel to the axis (25) of the said block, which itself is placed between the igniter (8) and the nozzle (16, 19) so that the said channels (24) are parallel to the axis (26) of the generator body, v) in the same transverse plane, the centres of the peripheral channels of the block (20) are not all equidistant from the centre (25) of the said block but are distributed alternately, in this plane, on two separate concentric circles (28, 29), and vi) the pyrotechnic charge comprises a material selected from the group consisting of a pyrotechnic composition based on nitrocellulose and nitroglycerine, and a plastic-bonded pyrotechnic composition essentially including a silicone resin as binder and a mixture of ammonium perchlorate and sodium nitrate as energetic charge.