Abstract: The adjustment of clearances at the time of assembly and subsequently during operation of a labyrinth seal lying between the rotor and stator of a turbomachine is effected by radial displacements of a bush radially rigid with an outer pivot pin of each blade of the stator and co-operates with a boss of the casing by means of screw-threads. Such displacements are controlled as a function of a signal provided by a computer which integrates various operational parameters of the turbomachine and acts on a control ring connected by a lever to the said bush. The internal pivot of the blade is rigid with an annular member which carries a layer of abradable material constituting a fixed part of the labyrinth seal. The rotary part of the labyrinth seal is mounted on an opposed part of the rotor. A method for effecting the adjustment of the clearances is also described.

Abstract: The connection between the actuating link of each variably settable vane of a compressor flow straightener in a turbine plant and the control ring for the vanes comprises a cylindrical roller rotatably mounted in a bore in the ring parallel to the axis of the compressor, the roller having a radial bore registering with a radial opening in the ring and housing the shaft of the link as a rotary and sliding fit. This arrangement prevents any torsional strain on the link during operation, and is found to be substantially simpler and more reliable than the known arrangements.

Abstract: A gas turbine engine for an aircraft comprises a gas generator which includes a compressor stage, a combustion chamber, and a turbine for driving the compressor, and through which the air and combustion gases flow from the rear towards the front in relation to the direction of travel of the aircraft before undergoing a reversal of direction to feed two contra-rotating power turbines which directly drive two contra-rotating airscrew or fan stages located near the front of the engine in the same longitudinal region as the power turbines. The gas generator is supplied by an air intake consisting of a plurality of ducts disposed around the outer casing of the engine, and the gases exiting from the power turbines are exhausted through a plurality of ducts positioned between the inlet ducts.

Abstract: A device for transmitting simultaneously to two parallel rods a motion with a single degree of freedom as a longitudinal translational motion from a sleeve surrounding the rods and which is itself subject to first and second degrees of freedom, a translational and a rotary motion, which includes a plate interconnecting the ends of the parallel rods, the plate lying perpendicularly to the axis of translational motion of the rods, and a connecting mechanism between the plate and the sleeve such that the connecting mechanism is adapted for transmitting only the translational motion to the plate.

Abstract: A turbine ring comprises an annular support in two parts and a ring of ceramic sectors for sealing purposes. The two parts of the support are interconnected by an axial groove and a sliding male part. Each part comprises an axial annular groove in which is engaged a respective axial edge portion of each sector. The cooperating internal radial faces respectively of the edge portion and of the groove are circumferential, while the radially outer radial face of each sector comprises at least one flat zone. The corresponding face of each groove may be polygonal.

Abstract: Method for the regeneration of machine parts of a nickel-based alloy, such as turbo-machine blades having reached the end of their useful operational life as a consequence of damage by creep in particular, consisting in holding the part for at least 1 hour at a temperature sufficient to redissolve a volumetric fraction of at least 50% of the .gamma.' phase, then controlling its precipitation by controlling the rate of cooling so as to regenerate its microstructural morphology.

Abstract: The metering device of the present invention is characterized by controlling the simultaneous relative positions of two sliding valve elements so that the degree of opening between fuel inlet and outlet orifices always corresponds to the setpoint of the fuel flow. If the position of either of the two sliding elements in the metering device of the present invention can no longer be controlled for whatever reason, such as being jammed, the other element may always be controlled to move relative to the jammed element such that the fuel flow may be controlled by the other element to correspond to that of the fuel flow setpoint. Thus, the metering device according to the present invention will continue to operate effectively even if the position of either of its slide elements can no longer be properly controlled, either because the element has jammed or because there has been a malfunction in its control system.

Abstract: The invention concerns a system for controlling heat expansion and thermal stress in a gas turbine disk. The system includes perforated plates mounted close to and facing at least one surface of the disk, particularly opposite its rim and around its thick inner bored section. Conduits are provided for bleeding cold air and hot air from various stages of the compressor or from the turbine and for injecting cold air toward the rim of the disk and hot air toward its thick inner bored section through the corresponding perforated plates at the beginning of each acceleration, and, preferentially, during deceleration, for injecting hot air toward the said rim and cold air toward said inner bored section. The invention applies particularly to gas turbines used to propel aircraft.

Abstract: A process is disclosed for the preparation of ceramic cores which includes injection by means of a press of low power of liquid wax into cavities of a ceramic core disposed in a mould of elastomer produced by moulding of a dummy core which is a replica of the core to be produced.

Abstract: A turbo-machine compressor which includes variable incidence stator vanes the angular adjustment of which is controlled by a control ring coupled to individual vanes by individual links. Each link has at least one contact surface on each of its longitudinal edges, such surfaces being either plane or convex. In the event of failure of any link, the change in orientation is controlled within narrow limits by contact with the contact surfaces of adjacent links which have not failed.

Abstract: An afterburner fuel injection system is disclosed which utilizes a plurality of individual fuel injectors displayed in a radial array around the periphery of a turbojet afterburner. An atomizing chamber is associated with each fuel injection conduit to achieve a homogeneous atomization of the fuel with the exhaust gases passing through the afterburner. Each fuel injector is individually connected to a fuel supply source and a source of purging air to minimize the delay in afterburner ignition and to prevent coking of the injector nozzles.

Abstract: A blade root sockets provided in the discs of a turbine rotor have passages for cooling air which are arranged to be variably blocked by closure means carried by the upstream and downstream ends of the labyrinth carriers disposed between the discs. The labyrinth carriers are of the pin-like type and are able to expand and contract in response to the temperature of the gas flow passing through the turbine, moving the closure means to open or close the passages. The positions of the closure means adjacent the passages are determined by the relative dimensions and the thermal expansion coefficients of the discs and the labyrinth carriers, and may be chosen to provide full cooling air flow during engine acceleration, a reduced flow during stable operation, and a very restricted flow to the first disc only during deceleration.

Abstract: The invention relates to an electro-hydraulic governor particularly for a turbo-jet engine.All of the electro-hydraulic or electro-pneumatic equipment units such as solenoid valves are arranged on a common plate face of the governor, the latter being provided with a printed circuit connection plate of which the substrate faces the plate surface.The hydraulic connections are made fluid-tight between the equipment units and the governor by means of apertures with seals therein, which apertures pass through the printed circuit plate.

Abstract: A method of measuring a characteristic, such as thickness, of a test part makes use of the variation in impedance of a coil in a senor caused by eddy currents generated as a result of the proximity of the test part. The sensor measures two orthogonal components of the complex impedance. In use the sensor is moved towards the test part until one component of the impedance reaches a predetermined value and the characteristic measured as the value of the other component. The first component is selected during calibration as that component which is most sensitive to variation in the distance between the sensor and the test part.

Abstract: A connection device is disclosed for connecting a burner ring or flame holder made of a composite material and having a "V"-shaped cross-section, to an afterburner chamber duct of a turbojet engine. The connecting device has a cylindrical portion and a trapezoidal portion. The cylindrical portion extends through hollow projections formed from the composite ring material and extending from the ring in an upstream direction. The converging, opposite sides of the trapezoidal portion bear against inner surfaces of the converging flanges forming the "V" cross-section of the ring. The cylindrical portion is then attached to the afterburner duct via a link-bar mechanism.

Abstract: A method for the assembly and connection of bodies, massive parts or powder grains, of alloys comprising at least 50% of nickel, cobalt or iron, comprises a preliminary operation of deposition at the interface of the said bodies of a product of the type MBF.sub.x, x being equal to 3 or 4, M designating a radical of the type NH.sub.4 giving off when hot a gaseous component such as NH.sub.3 or a metallic element and a sequence of treatment of cleaning/activation by passage of the coated body at a temperature in excess of the temperature of sublimation of the said product.

Abstract: A turbomachine rotor disc assembly includes a rotor disc having a plurality of blade-root grooves in its periphery, each two adjacent grooves defining a lobe lug between them. Rotor blades each include an aerofoil portion, a root portion, a platform defining the radially inner boundary of the aerofoil portion, and a stilt portion interconnecting the radially inner face of the platform and the root portion, a free space being defined between each adjacent pair of blades. The angular clearance of each blade in its groove is limited by wedges operative between adjacent blades on the stilts thereof and connecting members carrying the wedges secured to the rotor disc and capable of transmitting shock loads and distributing resultant forces over an adjacent sector of the rotor. The wedges are so dimensioned in relation to the dimensions of the stilts of adjacent blades that the angular clearance is limited to the permissible angular clearance of each blade during auto-rotation of the rotor.

Abstract: In the process for the machining of a rotary flat fluid-tight seal by grinding, the working surface of the grinding wheel has imparted to it an inclination with respect to the annular surface of the seal, in such a manner as to leave behind on the said surface of the seal traces which are termed "in half-sun" at the intersection of the grinding wheel and of the seal along a chord. The inclination is provided by modifying the height of one of two headstocks of a grinding machine and by pivoting the table of the grinding machine in a horizontal plane. The fluid-tight seal thus produced provides a leakage flow of lubricating fluid and thus can be used as an axial thrust seal and bearing of a rotary shaft, especially for pumps.

Abstract: Disclosed is a method of manufacturing a composite material burner ring made wholly of a composite material. The burner ring is manufactured by winding a carbon or ceramic type refractory material about a toroidal form until a specific material thickness is obtained. The burner ring elements, such as radial arms, fastening clips or fuel feed tubes are then fastened onto the winding. Each of the elements may be formed in mirror-image halves and may be assembled onto the burner ring body in adjacent pairs, each one of the pairs facing in an opposite direction. The winding of the composite material is continued until a final thickness is obtained, thereby integrally attaching the burner ring elements to the burner ring body. The assembly is then subjected to a carbonization or ceramization head treating process.

Abstract: An assembly of an electronic computer apparatus and a carrier therefor which includes a computer apparatus casing which includes at least one side wall a front wall, a rear wall, an upper wall and, a lower wall electrical connector mechanism mounted on the side wall, coupling mechanism by which the carrier can be coupled to the computer apparatus, the carrier including a rear wall, at least one side wall, an upper wall, a lower wall, an electrical connector mechanism mounted on the side wall corresponding to the side wall of the computer apparatus on which the corresponding connector mechanism is mounted, and a coupling mechanism carried by one of the upper wall and one of the lower wall and the rear wall and arranged to couple the carrier and the computer apparatus, the coupling mechanism of the carrier including a first part enabling coupling motion of the computer apparatus to the carrier in a direction from the front to the rear of the carrier until the connector mechanism of the computer apparatus are al