Abstract: A pyrotechnic cut-off device includes: a pyrotechnic igniter, a conductive portion and a movable piston, the piston being able to be displaced in a cavity along a direction of displacement following the actuation of the pyrotechnic igniter between a first position of passage of the current in the conductive portion and a second position of cut-off of the current, wherein the piston defines a first sealing portion having a narrowing of section along the direction of displacement, and the cavity has a wall defining a second sealing portion which extends on either side of the conductive portion and which has a narrowing of section along the direction of displacement, the first sealing portion being in contact with the second sealing portion along a contact surface extending on either side of the conductive portion when the piston is in the second position.

Abstract: Cryogenic propellant tank (1) for a spacecraft engine, comprising an external enclosure (10) defining an internal volume, characterized in that the internal volume of the tank comprises a primary volume (V1) and a secondary volume (V2) connected to the primary volume (V1) via a valve (20) configured to selectively allow a passage of fluid from the primary volume (V1) to the secondary volume (V2), or to isolate the secondary volume (V2) from the primary volume (V1), the primary volume (V1) having a primary orifice (11) adapted to be connected to a first pressurization source (41), the secondary volume (V2) having a supply orifice (4) adapted to be connected to a supply line of a spacecraft engine (30), and a secondary orifice (12) adapted to be connected to a second pressurization source (42).

Abstract: A pyrotechnic cut-off device includes: a pyrotechnic igniter, a conductive portion and a movable piston, the piston being able to be displaced in a cavity along a direction of displacement following the actuation of the pyrotechnic igniter between a first position of passage of the current in the conductive portion and a second position of cut-off of the current, wherein the piston defines a first sealing portion having a narrowing of section along the direction of displacement, and the cavity has a wall defining a second sealing portion which extends on either side of the conductive portion and which has a narrowing of section along the direction of displacement, the first sealing portion being in contact with the second sealing portion along a contact surface extending on either side of the conductive portion when the piston is in the second position.

Abstract: A valve includes a valve body provided with a plug, connected to an actuation system, an upstream duct, a downstream duct, and a purge duct provided with a shutter. The plug is movable in rotation about a longitudinal axis in the valve body, so that the rotation of the plug according to a first angular sector defines a flow between the upstream duct and the downstream duct, the rotation of the plug according to a second angular sector separate from the first angular sector shuts off the connection between the upstream duct and the downstream duct, and the rotation of the plug according to a third angular sector included in the second angular sector actuates the shutter so as to allow a flow from the upstream duct to the purge duct.

Abstract: A system for separating composites of a space launch vehicle, comprising non-pyrotechnic separating modules distributed between the composites to be separated and a device for activating the separation modules, which can generate the simultaneous activation of all of the separating modules. The activation device consists of a source of compressed gas, the outlet of which is connected to each separation module.

Abstract: A nozzle comprises a combustion chamber having a downstream end and a divergent formed of a cone-shaped wall extending between an upstream end and a downstream end. The upstream end of the divergent is connected to the downstream end of the combustion chamber by an intermediate ring having an upstream flange fixed on a fixing flange secured to the combustion chamber and a downstream flange connected to the upstream end of the divergent. The intermediate ring having an inner channel present between the upstream and downstream flanges of the intermediate ring. A material able to take heat from the ring is present in the inner channel.

Abstract: A difunctional biphenyl compounds corresponding to formula (I) wherein Alk, Alk? and R are as defined in the description. These compounds are suitable as hardeners for thermosetting resins, especially epoxy resins.

Abstract: A fire extinguisher includes a body defining a storage chamber containing an extinguishing agent, a gas generator configured to pressurize the extinguishing agent in order to dispense it outside the body through an exit opening. The exit opening is equipped with a misting nozzle, and the extinguishing agent has a solidification temperature less than ?10° C., the saturating vapor concentration of the extinguishing agent taken at ?10° C. and at 1 bar being less than the extinguishing concentration of the extinguishing agent determined according to the ISO 14520 standard for a heptane fire at 1 bar.

Abstract: A supply system for supplying a rocket engine with at least one propellant, the supply system comprising at least one supply circuit able to circulate the propellant, and at least one reservoir in fluid communication with the supply circuit via at least one communication pipe, so that a fluid contained in the reservoir can flow from the latter up to the supply circuit, and vice versa, via said at least one communication pipe, the reservoir being able to contain a volume of gas, and heating means able to vary the volume of gas in the reservoir, the heating means being configured to vaporize the propellant in the reservoir.

Abstract: The invention relates to a pressure sensor (10) comprising a cavity (12) containing a liquid, said cavity (12) being closed at a first end by a first diaphragm (20a) and at a second end by a second diaphragm (20b), and a measuring body (30) which comprises a strain gauge (31) positioned inside said cavity (12), characterized in that the measuring body (30) is mechanically connected only to one diaphragm among the first diaphragm (20a) and the second diaphragm (20b) by a connection member (50), the measuring body (30) comprising a shape having central symmetry and the connection member (50) being fastened to the center of symmetry of said measuring body (30).

Abstract: A method of winding a pre-impregnated fabric strip onto a sloping surface includes a step of deforming the pre-impregnated fabric strip by applying differing traction forces to the pre-impregnated fabric strip, the traction forces being directed in a longitudinal direction of the strip, the values of the applied traction forces differing across the transverse direction of the strip. The differing traction forces are applied by tensioning the pre-impregnated fabric strip between firstly a pair of brake rollers and secondly a traction device present downstream from the pair of brake rollers, the traction device driving the pre-impregnated fabric strip at speeds that differ across the transverse direction of the strip. The method further includes winding the deformed strip onto a surface of revolution of winding tooling including at least one portion that forms a nonzero angle with the axis of revolution of the surface of revolution.

Abstract: In order to provide a temporary connection between two structure elements, such as two parts of a space launcher or of another type of spacecraft or aircraft, a connection device with controlled separation comprises a thermally breakable layer, two thermal containment layers, between which the thermally breakable layer is arranged, and an electrically conductive element arranged between the two thermal containment layers in such a way as to heat the thermally breakable layer using the Joule effect when an electric current passes through the electrically conductive element.

Abstract: The invention relates to an antenna comprising a radiative antenna element able to emit a signal in at least two disjoint frequency bands and a waveguide covered by the radiative antenna element, comprising two nested resonant cavities, each single-mode or mostly single-mode in a separate frequency band.

Abstract: To enable a local connection with separation on command, a connection device (20) comprises a first base plate (24), a first connection wall (22) forming a protuberance from the first base plate (24) and having an internal surface (22A) delimiting an internal volume (V) located on the side of the first base plate, on a first side, and a first connection surface (22B), a second base plate (28), a second connection wall (26) fixed to the second base plate on a second side and with a second connection surface (26A) covering the first connection wall (22) so as to form a space (S) between the first and second connection surfaces, a bonding layer (30) arranged in the space and extending along at least two distinct directions, and a heat generating material (32) arranged in an internal volume so as to enable heating of the bonding layer.

Abstract: Cryogenic propellant tank (1) for a spacecraft engine, comprising an external enclosure (10) defining an internal volume, characterized in that the internal volume of the tank comprises a primary volume (V1) and a secondary volume (V2) connected to the primary volume (V1) via a valve (20) configured to selectively allow a passage of fluid from the primary volume (V1) to the secondary volume (V2), or to isolate the secondary volume (V2) from the primary volume (V1), the primary volume (V1) having a primary orifice (11) adapted to be connected to a first pressurization source (41), the secondary volume (V2) having a supply orifice (4) adapted to be connected to a supply line of a spacecraft engine (30), and a secondary orifice (12) adapted to be connected to a second pressurization source (42).

Abstract: The modular interface system comprises an interface part intended to be mechanically connected to a mechanical element forming part of a platform of a space craft, a multi-pronged structure provided, at a first end, with at least three feet and configured to form a mechanical link between, on the one hand, the interface part arranged at a second end opposite the first end and, on the other hand, respectively, a plurality of junction elements, each junction element being connected to one of the feet of the multi-pronged structure with which it is associated, and the junction elements being intended to be mechanically connected to a rear face of the antenna reflector.

Abstract: The invention relates to the field of cryogenics, and in particular to a device and a method for chilling down a cryogenic system (1). The chilldown device (100, 101) comprises a cryogenic fluid feed circuit (102, 103) and at least one atomizing nozzle (110) connected to said feed circuit (102, 103). The chilldown method includes feeding cryogenic fluid via a feed circuit (102, 103) to at least one atomizing nozzle (110) connected to the feed circuit (102, 103), spraying the cryogenic fluid through the at least one atomizing nozzle (110) as a spray (200) of cryogenic fluid, and projecting the spray (200) of cryogenic fluid against at least one zone to be cooled in the cryogenic system (1).

Abstract: A pyrotechnical gas generator includes at least one pyrotechnical charge, at least one ignitor, and a cylindrical casing enclosing the at least one charge and the at least one ignitor, the cylindrical casing having an axial direction and a radial direction and including an annular wall extending along the axial direction of the casing, and gas ejection holes arranged on the annular wall. Each gas ejection hole extends in a output plane forming a non-zero angle with a tangential plane which is tangent to the annular wall at the gas ejection hole.

Abstract: A device for dispensing a pressurized material, includes a body defining a pressurizing chamber containing a gas generator, and a tank containing the material to be dispensed, the tank being defined by an end wall having an outlet orifice. The device includes a piston, to move inside the body, separating the pressurizing chamber from the tank, the gas generator to trigger the dispensing of the material to the outside of the body through the outlet orifice by causing the piston to pass from a material-storage, first position to an end-of-material-dispensing, second position in which the piston faces the end wall. The piston, when in the first position, presents a housing that is closed by a fragile portion beside the pressurizing chamber and that is open beside the tank, the housing containing a striker element that is held in the housing and that defines a channel opening out into the tank.

Abstract: In order to provide a temporary connection between two structure elements, such as two parts of a space launcher or of another type of spacecraft or aircraft, a connection device with controlled separation comprises a thermally breakable layer, two thermal containment layers, between which the thermally breakable layer is arranged, and an electrically conductive element arranged between the two thermal containment layers in such a way as to heat the thermally breakable layer using the Joule effect when an electric current passes through the electrically conductive element.