Abstract: A triggered-stroke actuator with its piston being held stationary in an initial position prior to triggering. The piston (13) is installed in the body (12) facing propulsion means (15) and a locking arrangement (19) that includes a latch (30) and at least one flexible tongue (23) attached to the periphery of the piston and having a hook (25) engaged with an internal abutment, the latch being moved at the beginning of triggering.

Abstract: Pyrotechnic actuator in particular for lifting the hood of an automobile in the event of a collision with a pedestrian. The actuator comprises a return-braking arrangement (25) acting between the rod (17) and the body (13) of the actuator and having an inertial actuating threshold in order to brake the rod in return only if it is subjected to a force under a sufficient acceleration truly representative of a collision.

Abstract: The present invention relates to a method for crystallizing ammonium dinitramide (ADN), through spontaneous nucleation and crystal growth, from a solution containing said ammonium dinitramide (AND) dissolved in a solvent. Said solvent characteristically has a viscosity greater than or equal to 0.25 Pa s (250 cP) when said spontaneous nucleation is implemented. The ADN crystals obtained by said method have a median shape factor of 1 to 1.5 and are perfectly suitable for placement in the composition of energy materials.

Abstract: The present invention relates to solid compounds which generate hydrogen by combustion, and to a method for generating hydrogen based on the combustion of said compounds. Said compounds have a composition which includes at least one inorganic borohydride, selected from alkali borohydrides, alkaline-earth borohydrides and mixtures thereof, and at least one inorganic oxidant. Characteristically, said composition comprises sulfur. Said method is advantageously implemented for supplying hydrogen to a fuel cell.

Abstract: The invention relates to a safety device for raising the bonnet of a motor vehicle in the event of a collision with a pedestrian. The safety device includes a pyrotechnic actuator provided with a thrust piston secured to a mechanism for raising the bonnet and able to deploy the said mechanism which is itself secured to the said bonnet, and a blocking device intended to block the said actuator in a given position. The main characteristic of this device is that it is made up of a shock-absorbing device employed when a pedestrian hits the bonnet which has been raised, so that the assembly consisting of the bonnet, the raising mechanism and the piston can move under the effect of the impact while at the same time being retarded.

Abstract: The invention relates to a device for controlling the opening of the hood (1) of the engine compartment of a vehicle, connected to the vehicle body in a hinged manner for enabling it to partially open by rotating around the rear hinge toward the front of the vehicle from a position in which the hood (1) is latched to the vehicle body by means of at least one hook (18). This device comprises an impact detector mounted at the front of the vehicle and interacting with an actuator (19, 21) for controlling the unlatching of said hook (18) and comprises means for guiding the opening of the hood (1), these means for guiding the opening of the hood (1) comprising means for guiding the rear edge (1a) of the hood (1) in an essentially vertical direction.

Abstract: The present invention provides pyrotechnic gas generator compounds and a method of obtaining them. Said compounds have a composition which comprises: an oxidizing charge which comprises at least one inorganic perchlorate and which does not comprise a chlorine scavenger; and a crosslinked, oxygen-containing hydrocarbon binder obtained by crosslinking an elastomer in the presence of at least one crosslinking agent and at least one oxygen-containing plasticizer for said elastomer; said elastomer having a molecular weight of more than 200 000 and being preferably selected from polyesters and polyacrylates; said at least one oxygen-containing plasticizer being composed of a plasticizer of which the molecular weight is greater than 350 g/mol and the oxygen balance equal to or greater than ?230 %, of a mixture of such plasticizers with one another or of a mixture of at least one such plasticizer with at least one other oxygen-containing plasticizer. Said compounds can be obtained continuously by extrusion.

Abstract: The main subject of the present invention are solid compounds capable of generating hydrogen by a self-sustaining combustion reaction. Their composition comprises borazane and/or polyaminoborane and at least one inorganic oxidant, advantageously chosen from ammonium nitrate, alkali metal nitrates, alkaline-earth metal nitrates, metal nitrates, metal oxides, oxidants of the family of dinitramines and mixtures thereof. It also relates to the generation of hydrogen by self-sustaining combustion of at least one such compound.

Abstract: The triggered stroke actuator comprises a cylinder (12) housing a movable assembly constituted by a piston (13), a rod (16) projecting from one end of the cylinder (12), and a slidable element (17) that is movable inside the cylinder (12). The actuator also includes means for propelling the piston (13) in response to a trigger command, and a return braking arrangement. The return braking arrangement is constituted by at least one ball (18) housed in an annular cavity (19) defined by the inside surface of the cylinder (12) and by the slidable element (17), a return spring (22) connecting the slidable element (17) to the piston (13), and a link element (23) connecting the ball (18) to the piston (13). The ball (18) is positioned by the link element (23) in a first segment (20) of the annular cavity (19) when the return spring (22) is relaxed, and in a second segment (21) of decreasing radial extent when the return spring (22) is compressed.

Abstract: A subject matter of the present invention is compositions which generate nitrogenous gas, with a low decomposition temperature, and processes for the generation of nitrogenous gas comprising the decomposition of such compositions. Said compositions comprise: from 20 to 80% by weight of azodicarbonamide, from 20 to 80% by weight of a nitrogenous reducing charge, from 0 to less than 10% by weight of at least one additive; said azodicarbonamide and said nitrogenous reducing charge representing at least 90% of their weight and said nitrogenous reducing charge comprising: at least one compound from a first family of reducing components chosen from tetrazole, tetrazole derivatives and their salts, salts of bitetrazole and of its derivatives, 5,5?-azobitetrazole salts, polyvinyltetrazoles and their mixtures; and/or at least one compound from a second family of reducing components chosen from dicyandiamide, 1-hydrobenzotriazole, silicon nitride, nitroguanidine, guanidine nitrate and their mixtures.

Abstract: Subjects of the present invention are: a method of desensitizing crystals of an energetic explosive substance by coating them, said method comprising the deposition, carried out within a fluid, outside the normal temperature and pressure conditions, preferably under supercritical conditions, of a metal and/or polymer film, advantageously of a metal film or of a polymer film, on the surface of said crystals, the metal(s) and/or polymer(s) in question having been firstly dissolved in a solvent; the coated crystals of an energetic explosive substance obtainable by said method; and the energetic materials containing said crystals coated by said method and/or said crystals desensitized by said method.

Abstract: The present invention relates to a process for the preparation of novel ammonium dinitroamide (ADN) crystals and to said novel ADN crystals. Said novel crystals have an original morphology factor, namely a low shape factor. They are obtained in the presence of at least one crystal habit modifier.

Abstract: A subject matter of the present invention is: the compounds of formula (I): in which: and Het is an azolyl radical: nitroazolyl or tetrazolyl; with the exception of 3-nitro-4-(4-nitro-1,2,3-triazol-1-yl)furazan; the preparation of said compounds; and the energetic compositions including at least one compound chosen from said compounds of formula (I) and 3-nitro-4-(4-nitro-1,2,3-triazol-1-yl)furazan.

Abstract: The invention relates to a method and to an autonomous device (10d) for injecting a fluid (F), that uses pyrotechnical means (1d). The invention can be used in particular for injecting a protection fluid (F) into a system that is subject to overheating (8d). The method is characterised in that it uses a thermally triggered charge (1d).

Abstract: The subject of the present invention is a pyrotechnic method for generating gas at two successive flow rates a first flow rate then a second flow rate, said first flow rate being higher than said second flow rate—which comprises: the combustion of a first pyrotechnic charge (10) in a first combustion chamber (1) discharging into a second combustion chamber (2) via at least one nozzle (3); and the combustion of a second pyrotechnic charge (20) in said second combustion chamber (2) discharging to the outside via at least one vent (21). Characteristically, said first chamber (1) operates at high pressure and said second chamber (2) operates at low pressure. Another subject of the invention is a pyrotechnic gas generator suitable for the implementation of said method. The invention is most particularly applicable in the context of side protection airbags (“curtain airbags”), used in automobile safety.

Abstract: The present invention provides pyrotechnic grains of composition comprising at least one oxidizing charge and at least one reducing charge and no binder. In characteristic manner, said grains are in the form of substantially cylindrical blocks: with a thickness of more than 5 mm; with an equivalent diameter of 10 mm or more; and with porosity in the range 1% to 8%, limits included. Said grains, advantageously based on guanidine nitrate and basic copper nitrate, are suitable for the slow, low-pressure generation of gas over an extended period.

Abstract: The subject-matter of the present invention is: pyrotechnic compositions generating gases, whereof at least 95% by mass of the charges are constituted by constitutive ingredients hereinbelow: a reducing charge in the form of at least one organic nitrogen compound; an oxidizing charge in the form of at least one basic metal nitrate; and less than 30% by mass of a second oxidizing charge in the form of at least one alkaline metal perchlorate; and which are obtained via a dry roller compacting step of a pulverulent mixture essentially constituted by said powder ingredients; and also the method for obtaining such compositions. The compositions of the invention have interesting combustion speeds.

Abstract: The invention relates to a thermal erosion test device for testing thermal protection materials for use in a solid propellant thruster. The device comprises a support for holding a plate made of the thermal protection material for testing so that its faces a face of a block of solid propellant, the space between the plate and the face of the propellant block defining a combustion chamber of substantially rectangular shape, said chamber extending along said plate and opening out into a nozzle.

Abstract: The invention relates to a microsystem and a method for fabricating a microsystem. The pyrotechnic microsystem (7, 1?) comprises a substrate having at least two separate electrical initiation zones, each of which provides separate electrical initiation of a pyrotechnic material deposited on the substrate. This microsystem (7, 1?) is characterized in that the same pyrotechnic material deposit (721, 721?, 13) covers both initiation zones, said deposit (721, 721?, 13) produced on the substrate having a thickness sufficiently small for the initiation of the pyrotechnic material in the initiation zone to remain localized and not propagate to the other initiation zone, but sufficient to generate a specific gas quantity.

Abstract: The present invention relates to a dry process for the manufacture of pyrotechnic objects from at least one reducing charge selected from guanidine derivatives, metal hydrides, alkali metal hydrides and alkaline earth metal hydrides, and at least one oxidizing charge selected from alkali metal nitrates, alkaline earth metal nitrates and basic metal nitrates, at least one of said reducing and oxidizing charges having the property of flowing under stress. Said process makes it possible to obtain pellets and small tablets directly by compaction/compression, to obtain granules, usable as such, by compaction and then granulation, and to obtain compressed objects by compaction, granulation and then compression. The high-performance pyrotechnic objects obtained constitute a further subject of the invention.