Abstract: A fuel injection supply circuit including a main filter situated between a low pressure pump and a high pressure pump, and a fuel metering device for supplying a metered flow of fuel to the fuel injectors, is provided with a self-cleaning filter downstream of the high pressure pump such that a first portion of the fuel flow received by the self-cleaning filter is filtered to provide a clean flow of fuel to the fuel metering device and the excess portion of the received fuel flow passes through the center of the self-cleaning filter and is returned, via a control valve, to the circuit upstream of the main filter.

Abstract: A bypass engine including a fan which has its blades disposed in both the imary gas flow path and the secondary gas flow path of the engine is provided with an annular intermediate gas flow path in the space between the primary and secondary flow paths, and gas take-off means is connected to a compressor of the engine and arranged to direct a flow of gas longitudinally along the intermediate flow path to prevent leakage of hot gas to the secondary flow path via the gaps existing between the platforms of the fan blades and the adjacent annular members of the primary and secondary flow paths.

Abstract: A packing member for restraining the root of a fan blade in a socket of a rotor disk takes the form of a curvilinear plate comprising a metallic sub-structure having recessed portions and a semi-rigid elastomeric material molded into and filling the recessed portions. The member has a substantially metallic central area extending as far as the side edge of the member on the same side as the extrados face of the blade, the metallic central area having a machined profile set back relative to the profile of the socket so as to permit the root of the blade to rock in response to a violent impact on the blade. The packing member has upstream and downstream end areas which are entirely metallic, and the two side edges of the member upstream and downstream of the central area are defined by the elastomeric material. Between the two elastomeric side edges, both upstream and downstream of the metallic central area, the member has a metallic lower part and an upper part formed by the elastomeric material.

Abstract: A digital frequency demodulator includes a first counter and a second counter measuring the instantaneous and mean values of the period of a frequency modulated signal. A comparator compares the values measured and creates a binary signal of the same frequency as the modulation signal. The measurement of the instantaneous value of the frequency modulated signal is effected by counting the number of reference clock pulses during a period of the modulated signal, and the measurement of the mean value is effected by counting the number of pulses of a clock signal of frequency N times lower than the reference clock during N periods of the modulated signal.

Abstract: A labyrinth disk includes a main stiffener placed in the middle of the rim immediately below labyrinth elements. Attachment elements are preferably in the form of a bayonet attachment system using teeth fixed on the labyrinth disk crown and teeth fixed on the rotor. Attachment by bolting may optionally be used. The disk may be utilized with turbojets, on the cooling circuit, on the upstream side of the high pressure turbine.

Abstract: A nickel-based superalloy possessing good mechanical properties when hot regarding traction, creep and cracking resistance has a chemical composition which comprises, in percentages by weight: Co 14.5 to 15.5 ; Cr 12 to 15 ; Mo 2 to 4.5 : Al 2.5 to 4; Ti 4 to 6; Hf not more than 0.5 ; C 100 to 300 ppm; B 100 to 500 ppm; Zr 200 to 700 ppm; possibly W up to 4.5; and nickel as the remainder. Components made from these alloys have an excellent microstructural stability when operating at temperatures up to 800.degree. C.

Abstract: Manual rotation of a turbomachine rotor in order to bring the blades of the rotor one by one in front of an endoscope to check the blades is effected by a shaft which is rotatably connected to the rotor and which may be, for example, a shaft of the auxiliary equipment of the turbomachine, the shaft being manually rotatable by a driving shaft which is mounted in an opening in the casing housing the shaft and which is engageable with the shaft by self-disengaging coupling, a seal being provided between the driving shaft and the casing.

Abstract: A cooling device for an aircraft turboshaft engine includes a boundary layer suction device formed by a perforated external wall portion of the aircraft, a collector on the inside of the wall portion for receiving the air flowing in through the perforations, and a discharge device discharging the air from the collector. The cooling device is completed by a heat exchanger which is disposed in the path of the air flow through the collector, a pump for pumping fluid to be cooled through the heat exchanger from a circuit of the engine, and a regulator regulating the fluid flow through the exchanger to control the temperature of the fluid. The fluid which is cooled may be from the lubrication circuit, the fuel circuit, or an air circuit of the engine, and the boundary layer suction device is preferably disposed in the pod of the engine.

Abstract: A device for suspending a turboprop engine from a structural element of an aircraft comprises a suspension pylon parallel to the longitudinal axis of the engine and fixed to the structural element, resilient connections between the engine and the pylon and an arch fixed to the pylon, and a torsion bar carried by the arch so that the bar can pivot freely about its own axis, the opposite ends of the torsion bar being connected to opposite sides of the engine by respective lever and link rod assemblies so that the torsion bar takes up the reaction torque about the longitudinal axis of the engine.

Abstract: Device for cooling the external part of a turbine disk (2) by means of an external fresh air current (circuit II) without mixing with the warmer ventilation from the center of the disk (circuit I). A part (30) through which ducts (31, 32) pass that intersect without interruption, prevents mixing of substantially perpendicular streams in front of a part (22) of the disk (2) and a mixture which reduces the cooling efficiency.

Abstract: A differential pressure detector for providing an output pressure modulated as a function of the pressure drop between the pressures upstream and downstream of a fuel metering device, comprising first and second input chambers for connection to said upstream and downstream pressures respectively, a modulated pressure output chamber, a sleeve which is linearly movable in response to changes in the difference between the pressures in the first and second input chambers, and a fixed slide valve which is partly received in the sleeve and which has a bore opening into the output chamber and at least one side port for communicating the first input chamber with the output chamber via the slide valve bore, the aperture of the side port being varied by linear movement of the sleeve to control the communication between the first input chamber and the output chamber. The detector has reduced reaction forces and is particularly suitable for use in a fuel flow regulating system.

Abstract: A device for actively controlling combustion instabilities and for decoking uel injectors comprises at least one detector for measuring pressure fluctuations in a combustion or afterburner chamber, means for processing the signal output by the detector and providing, in turn, a control voltage, and at least one piezoelectric device which is disposed in a hydraulic line including a fuel injector for the supply of fuel to the combustion or afterburner chamber and which is responsive to the control voltage to generate pulses in the flow of fuel from the outlet of the fuel injector.

Abstract: Pivoting vane internal extremity bearing (1) whose internal extremities are connected by a linking ring (12). The bearing elements (18) connecting the internal extremity pivots (10) to the ring (12) are composed of a bush (19) prolonged by bearing necks (20) with a spin axis (X') parallel to that of the ring (12). The forces undergone by the vanes, which transversally move the pivots (10), do not cause any wear of the bush (19), but a rotation of the latter around the axis (X'). Application for turbine aero engine stator vanes.

Abstract: A control device for the pivot of a variably settable movable vane mounted so that the pivot is integrated in an air manifold comprises a rotatable mounting for pivotally mounting the pivot in a bore in a platform fixed to the manifold by upstream and downstream flanges, a link for rotating the pivot to vary the setting of the vane, and a ring mounted outside the manifold and connected to the link for controlling the setting of the vane. The rotatable mounting for pivotally mounting the pivot in the bore comprises an end piece which is fitted on the pivot and which itself fits within a hollow friction bush fixed in the bore. The bush is provided with a slit extending partly around its circumference, and the upstream end of the link projects through the slit via apertures in the manifold and the platform to engage with an eye provided on the pivot end piece which receives a correspondingly shaped intermediate portion of the end piece.

Abstract: Damping disposition for vanes (3) fitted with stilts (4, 5) engaged in the alveoles of the rotor disk (1). Damping elements (10) are added including a portion (11, 12) extending along the flanks (6) of the stilts (4) and including a portion (15) leaning against them. The beating vibrations of the vanes (3) and dampened by these elements able to be used on smooth vanes without any platform, such as large blower vanes. Application for turbo-engines.

Abstract: A process for joining two parts of which at least one is made of an intermetallic material comprises:mixing elemental powders to form an intermetallic compound of the same type as that of the intermetallic part or parts;compacting and forming an intermediate part from the said compound at a temperature below that of the reaction sintering temperature of the compound;placing the intermediate part in position between the two parts to be joined;subjecting the assembly of parts to a first thermal cycle so as to effect a reaction sintering of the intermediate part and a consolidation of the assembly; and,subjecting the assembly to a second thermal cycle at a temperature above 0.8 of the fusion temperature of said intermetallic compound so as to effect a diffusion treatment and mechanical consolidation of the assembly.The process may also be adapted to form a coating or a repair of a part using an intermetallic material.

Abstract: A valve is disclosed which is adapted to be disposed between a first chamber and a second chamber for the purpose of selectively interconnecting the two chambers or isolating them from one another. The valve comprises a body, a sleeve disposed therein and provided with a number of orifices which open into a first duct in the body for the delivery of fluid to the second chamber, and a piston which is slidable in the sleeve to close or open the orifices and which separates a feed chamber communicating with the first chamber from a control chamber communicating, by way of a second duct, with the throat of a venturi formed in the first duct. The opposite faces of the piston are thus both exposed to the fluid, and a spring is provided in the control chamber for biassing the piston towards closing the orifices.

Abstract: A combustion chamber, particularly for a turbomachine, has at least one generally axially extending wall provided with a plurality of through holes defining a multi-hole cooling system for the wall. The wall also has a plurality of dilution holes which affect locally the flow of burnt gases in the chamber, and the cooling through holes are oriented according to the local flow of burnt gases in the chamber. In particular the wall is subdivided into first zones, downstream of the dilution holes, in which the through holes are oriented substantially in countercurrent to the overall flow direction of the burnt gases in the chamber, second zones and third zones which are disposed on opposite sides of the first zones and in which the orientation of the through holes is inclined both axially and circumferentially, and a fourth zone covering the remainder of the wall and in which the through holes are inclined axially in the overall flow direction of the burnt gases.

Abstract: Oil separator rotor located in an enclosure provided with an oil reinjection system for lubricating a bearing. The oil separator rotor, which dries the excess air passing out of the enclosure, acts by aiding the deposition of suspended oil on the walls of a lining or packing of the rotor. The lining is a honeycomb material cartridge offering easy separation without excessive pressure losses. The rotor is assembled by bolts, which interconnect the end plates traversing the lining.

Abstract: Device for joining turbine engine distributor segments (22) to a casing (3). The pins (13) for stopping the rotation of the segments (22), engaged in notches (26) of the latter, are separated from a casing-abutment flange (23) by a continuous partition (27), which prevents any air leak. (FIG.