Abstract: A cooling device for cooling disks of high-pressure and low-pressure turbines of a turbomachine, said device being fed with cooling air from at least one air orifice formed through a bottom annular platform for supporting at least one fixed vane of said low-pressure turbine and being disposed between an upstream flange and a downstream flange of said bottom platform, the device comprising: an upstream annular plate extending radially from the upstream flange of said bottom platform; a downstream annular plate extending radially from the downstream flange of the bottom platform, said upstream and downstream plates longitudinally defining at least one annular cavity for cooling air; a sealing device extending longitudinally between said upstream and downstream plates so as to close the cooling air cavity in leaktight manner; holding means for holding said upstream and downstream plates against the upstream and downstream flanges of said bottom platform; and a plurality of holes for injecting cooling air towards

Abstract: A system for decoupling a fan of a turbojet, the turbojet including a moving fan shaft mounted on bearings each connected to a stationary structure of the turbojet by bearing supports, the bearing supports being fixed to the stationary structure of the turbojet via mechanical links serving, during normal operation of the turbojet, to transmit the forces generated by rotation of the fan, the mechanical links include explosive charges enabling the links to be broken, the explosive charges being controlled by a full authority digital engine control computer on the basis of means for measuring the mechanical stresses in the turbojet and of a computer model simulating the static, dynamic, and thermodynamic behavior of the turbojet.

Abstract: An annular platform for the nozzle of a low-pressure turbine in a turbomachine, said nozzle having a longitudinal axis and comprising at least one fixed vane disposed downstream from at least one moving blade of a high-pressure turbine, said platform comprising a downstream portion supporting said fixed vane radially defining an aerodynamic channel which extends longitudinally between a leading edge of said fixed vane and a trailing edge of said moving blade, said platform further comprising an upstream portion extending longitudinally beyond the leading edge of said fixed vane towards the trailing edge of said moving blade so as to lengthen said aerodynamic channel.

Abstract: A flange covering a disc of a turbine blade to allow ventilation. A diverted face of the disc is provided with a labyrinth seal with lickers to form a seal. Cutters of the lickers are inclined axially and staggered axially and radially, to off-set the center of gravity of a flexible web of the disc and to encourage deformation of the web towards the disc under the effect of centrifugal forces, to reinforce the contact of a bearing face with a pressure plate of the disc. Thus, hooks usually used to unite the periphery of the web to the disc become superfluous.

Abstract: An injector of a two-headed combustion chamber of a turbomachine has a first feed tube which is connected to an annular injection piece for discharging primary fuel into the combustion chamber. It also has a second feed tube surrounding the first feed tube and connected to a cylindrical endpiece for discharging secondary fuel into said combustion chamber. This endpiece has an annular channel of diameter that is greater than the diameter of the second feed tube and that extends over its entire length. A third tube is provided that surrounds the second tube and that is connected to a tubular separation element which is inserted in the annular channel of the cylindrical endpiece so as to form two annular spaces in which a cooling fluid can flow over 360° all the way to the end of the injector.

Abstract: The retaining device (110) designed to retain a portion (59) of a part connection device (52), said portion (59) of the connection device (52) being released during failure of said connection device (52), comprises:

Abstract: The invention provides a system for passively controlling pressure oscillations of hydrodynamic origin in a solid propellant thruster comprising a body containing a charge of solid propellant, the system comprising at least one insert disposed in the thruster body transversely relative to the flow direction of the combustion gases of the solid propellant. The insert has an opening of non-axisymmetric shape so as to generate a three-dimensional effect on the flow and prevent axisymmetric turbulent modes from forming in the thruster. Thus, the control system of the invention serves to break the symmetry of the flow and thus prevents axisymmetric turbulence forming which is the source of instability that the present invention seeks to control. The present system is applicable to existing thrusters.

Abstract: The pivots (2) of the blades (1) comprise removable portions (16) located at their outer end and adjustable in height using a thread (17) or a similar means in order to adjust the distance between the head (9) of a lever (10) controlling the adjustment of the blade and the casing (4) or the collar (8) of a bearing (5); if the centring bushings (7) of the bearings (5 and 6) are worn, harmful tilting of pivots (2) will be limited by a stop for the head (9).

Abstract: An electrohydraulic device for varying the pitch of the blades of a machine rotor, the blades being mounted on a hub rotated by a drive shaft of the machine, and each blade having a root capable of pivoting about a longitudinal axis of the blade, the drive shaft itself being rotated relative to a stationary structure of the machine, the device comprising firstly a hydraulic actuator whose piston is secured to a control and synchronization ring in which off-center wrist pins are engaged, each fixed in register with one of said blade roots, and having a cylinder closed by a cover that includes a high pressure hydraulic pump feeding hydraulic fluid to both faces of said piston via channels integrated in said cylinder of the actuator, and secondly an electric motor controlled and powered by an electricity generator comprising an inductor secured to said stationary structure of the machine and an armature secured to said drive shaft of the machine.

Abstract: The invention provides a cryogenic valve device comprising a valve body in which a cryogenic fluid flows, and a valve member disposed in the duct and connected to a control rod for moving the valve member between a closed position and an open position so as to control the flow rate of the cryogenic fluid. The device further comprises a pneumatic actuator having a chamber containing a piston in connection with the control rod, the chamber being fed with control gas to position the piston in a determined position. The actuator is fixed to the valve body via a chamber interposed between the actuator and the valve body in such a manner as to decouple the actuator thermally from the valve body so as to maintain the temperature of the actuator, and consequently the temperature of the control gas, at a temperature that is intermediate between the temperature of the valve body and ambient temperature.

Abstract: In order to enable the information contained in an identification connector to be read in a manner that is more reliable, faster, and without risk of damage, the invention provides a reader appliance for reading identification connectors for airplane engines, the connector comprising a plurality of contacts connected to a decoding circuit, each contact corresponding to a binary digit, one or more of the binary digits corresponding to information relating to characteristics of the engine. The reader appliance comprises connection means suitable for receiving at least one identification connector, the connection means being connected to processor means responding to control members in order to display on a display device the information contained in the connector.

Abstract: A jet engine suspension includes a master component for attachment, fixed to an aircraft pylon. In the event of breakage of the master component and in the situation where the fixing screws are no longer able to transmit force, a peg is provided which resists transmitted loads such that the master component collapses until an upper shoulder rests on the pylon and supports the master component. The peg is free of dynamic stress in normal service and there is absolutely no risk of it cracking in fatigue.

Abstract: A device for electrical discharge machining at least one rectilinear cooling air passage having a flared opening in the wall of a hollow turbine vane. The device includes at least one forming electrode attached to a first electrode holder and includes a first face provided with a groove for guiding a rectilinear electrode configured to drill the rectilinear part of the air passage, a median portion with a constant section, and a pointed end portion with a section that decreases between the median portion and the point of the forming electrode.

Abstract: The invention relates to a fan rotor comprising a disk having a rim with a plurality of substantially axial grooves that are regularly spaced apart angularly, a plurality of removable blades extending radially outwards from the periphery of said disk, each blade having a blade root received in a respective groove, a downstream flange plate secured to said disk with the downstream faces of the blade roots being in abutment thereagainst, and a removable upstream flange plate secured to said disk for the purpose of retaining the blade roots in the grooves. In the rotor, the upstream flange plate is fitted on its downstream face with resilient means for exerting sufficient force on the upstream faces of the blade roots, after assembly, to prevent any axial displacement of the blades during normal operation of the engine (apart from exceptional events of the type in which foreign bodies are ingested or blades are lost).

Abstract: A method for the early detection of aerodynamic instability in a turbomachine compressor is described which involves collecting and normalizing signals from sensors distributed uniformly around the circumference of the compressor and detecting events for which the normalized signals do not pass through a zero value during a length of time Tz which is at least greater than the time taken for two successive moving blades to travel past the sensor. A decision regarding the imminence of aerodynamic instability is then taken after the detected events have been analyzed and decision criteria have been applied. The decision criteria may be based on the event detection rate and/or on the spatio-temporal position of the events detected across all the sensors.

Abstract: The method of the invention enables a coating to be made on at least one face to be protected of a metal substrate and/or article in order to improve its performance in terms of resistance to wear by friction, in particular at high temperature.

Abstract: The invention relates to a device for immobilizing blades in the peripheral slot of a turbomachine disk. Said blades comprise roots of the hammer head type adapted to be introduced into said slot through a loading window and held in said slot by collaboration of shape with the sidewalls thereof. Said immobilizing device is adapted to be introduced into said slot through said loading window and comprises a locking element arranged in a space separating two adjacent blade roots. Said locking element is adapted to be raised up into a lock housing formed in the sidewalls of said slot under the action of a radial manipulating screw the head of which rests against the bottom of the slot, a radial clearance being provided between the bottom of the slot and the underside of the blade roots, and said screw head being restrained in a radially outward direction by said two adjacent blade roots.

Abstract: A powder material for forming an abradable coating, the material comprising a metal powder based for the most part on aluminum and containing manganese or calcium. The material is applicable to seals of a turbomachine.

Abstract: An oxidation-sensitive composite has applied thereto a composition comprising a mixture of boride powder constituted for the most part of TiB2, at least one vitreous refractory oxide powder constituted for the most part by a mixture of borosilicate glass, and a binder containing a ceramic-precursor resin. The resin is cured and is subsequently transformed into a ceramic by heat treatment or during first exposure of the coated part to high temperatures.

Abstract: The method is used to attach the various parts of a “T” assembly using a single laser welding pass from the outside of the “T” assembly.