Societe Nationale D'etude Et De Construction De Moteurs D'aviation

Snecma Moteurs

Snecma

Other

Safran Aircraft Engines

Hispano Suiza

Societe Nationale D'etude Et De Construction De Moteurs D'aviation-snecma

Jean-Marie Brocard

Claude M Maillard

Philippe Galozio

Pierre G Hebert

Alain Tiepel

Guy D'Agostino

Eric C Lorne

Franck Liotte

Alain Varizat

Pierre Charles Mouton

Regis Michel Paul Deldalle

Marie-Trinit&eacute; Rose Blot-Carretero

Michel Martini

Jean-Yves L Bezard

Maurice G Vernochet

Eric Perrodeau

Michel A Desaulty

Marion Michau

Daniel Germain Kettler

Michel M Lechevalier

Alain Pierre Garassino

Alain Lavie

Christian A Parisel

Jean-Yves Capelle

Jean-Paul Perrin

Christian LaCour

Alain Michel Varizat

Guv d'Agostino

Thierry N De Jongh

Marie Trinit&eacute; Blot-Carretero

Michel Francedillaois Le Texier

Alain Sartori

Bertrand Esquevin

Christian Leboeuf

Philippe Prades

Alain Patrick Paya

Christian Denis Le Boeuf

Marie-Trinit&euml; Rose Blot-Carretero

Michel Le Texier

Regis Deldalle

Anne Marie Cecile Barreau

Anne Marie Cécile Barreau

Régis Michel Paul Deldalle

Marie-Trinite Rose Blot-Carretero

Claude Marcel Maillard

Régis Deldalle

A fuel metering unit comprising a movable element including at least one fuel flow section opening upstream towards a fuel supply duct and opening downstream towards a utilization duct through a metering slot with a flared profile having a narrow flow section and a wide flow section, the movable element able to be moved with respect to a stationary element between a low flow rate position and a high flow rate position, the metering slot made in the stationary element or in the movable element and its obstruction obtained by covering the slot with a wall of the movable element or of the stationary element.

Fuel metering device protected against icing

A fuel metering unit including a movable element including at least one fuel passage section opening upstream towards a fuel supply conduit and opening downstream towards a conduit of use through a metering slot with a flared profile having a narrow passage section flaring as far as a wide passage section, the movable element being able to be moved with respect to a fixed element between a low flow rate position in which the metering slot is for a large part obstructed and a high flow rate position in which the metering slot is for a large part exposed, the metering slot being made in the fixed element or in the movable element and its obstruction being obtained by covering the slot with a wall of the movable element or of the fixed element.

Fuel meter protected from icing

A fuel supply device includes a fuel supply pipe receiving fuel at a non-regulated pressure delivered by a pump, a device for measuring the flow rate of fuel in the pipe, a first controlled variable-restriction valve mounted in the supply pipe, a control system connected to the flow rate measurement device and to the first valve to control the valve to deliver fuel to the engine at a desired flow rate under normal operating conditions of the engine, a second controlled variable-restriction valve mounted in the supply pipe in series with the first valve, and a control for controlling the second valve to enable the engine to be supplied with fuel at an adjustable, reduced flow rate in response to detecting over-speed or over-thrust of the engine.

Device for supplying fuel to a gas turbine engine with regulated fuel flow rate

A centrifugal pump driven by mechanical coupling with an engine has a low pressure inlet receiving fuel from a fuel circuit of an aircraft, a high pressure outlet connected to a regulator circuit for regulating the flow rate of fuel supplied to the engine, and an assistance pump unit that is electrically controlled, having an inlet connected to the aircraft fuel circuit and an outlet connected to the flow rate regulator circuit so as to deliver, via its outlet, fuel that is at a predetermined minimum pressure, the pressure of the fuel supplied to the regulator circuit being the higher of the pressures delivered by the centrifugal pump and the assistance pump unit.

Aircraft engine fuel supply

The actuator assembly comprises a master actuator and at least one slave actuator having a cylinder containing a piston defining two chambers in the cylinder. A first chamber of the slave actuator is connected to an outlet of a directional control valve which is connected to a hydraulic control circuit and to a control member whose position determines the pressure in the first chamber of the slave actuator. A displacement of the piston of the master actuator is transferred to the control member of the control valve associated with the slave actuator by means of a mechanical transmission such as a flexible linear rolling bearing. Thus, the displacement of the piston of the slave actuator is servo-controlled to the displacement of the piston of the master actuator by controlling the position of the control member of the control valve associated with the slave actuator. The actuator assembly is suitable for use in particular for controlling the moving flaps of the nozzle of a turbojet of variable exhaust section, and possibly also steerable.

Actuator assembly with synchronized hydraulic actuators

An aircraft engine fuel supply circuit includes a high pressure pump for supplying the engine fuel injectors and supplying a plurality of servovalves for operating various auxiliary mechanisms. In an in-flight re-ignition configuration, with the rotational speed of the engine drops below a threshold value, a fuel economizer valve receives a command to close, thereby shutting off the supply of high pressure fuel to the servovalves. Consequently, the dimensions of the high pressure pump and other associated components in the circuit, especially heat exchangers, may be reduced.

Device for economizing fuel supply in a fuel supply circuit

The servovalve comprises an electric motor and a distributor valve integrating a hydraulic slide under the control of said electric motor and further comprising two load channels pierced in a central rod on which blocks are mounted for co-operating with communication orifices of the distributor valve and co-operating with one another and with the ends of the hydraulic slide to define annular chambers including two load chambers connected to the receiver member to be controlled. The two load channels put each of the load chambers into communication respectively with an immediately adjacent annular chamber so as to ensure that the same pressure exists on both sides of the blocks separating said two chambers. In a predetermined safe position (referred to a &ldquo;fail-freeze&rdquo; position) in which the blocks close the load orifices with clearance, the leaks through the load orifices that result from the clearance are drained at determined low pressure, thus enabling the drift of the controlled member to be controlled.

Fail-freeze servovalve

A device for controlling fuel pressure and delivery as necessary for the operation of the servovalves of an aircraft engine is disposed downstream of a fuel injector feed unit of the engine. The device comprises a chamber maintained at the servovalve feed pressure by the movement of a closure member to vary the opening of a port of the chamber. The closure member moves under the action of opposing forces comprising inter alia a force in the opening direction proportional to the servovalve feed pressure. An equilibrium position of the closure member is a function of pressure resulting from the engine speed. An injector delivery control loop is therefore isolated from a servovalve pressure and delivery control loop.

Process for controlling the pressure and delivery of a fuel feed to a servovalve unit

Device for controlling the pressure and delivery of a fuel feed to a servovalve unit

A hydraulic fuel control unit ( ) for an aircraft engine comprises means ( ) for controlling cutoff on stop and cutoff on overspeed of a fuel flow transferred by an output ( ) to the engine injectors. A logic module ( ) controls the position of a state switch ( ) into a test position or a normal position. The state module is managed such that the operation of the overspeed module can be tested each time the system is started on the ground. The architecture of the hydraulic unit ( ) is such that operation of the cutoff on stop can be tested during each landing. Correct operation in the overspeed test and in the cutoff on stop test is observed by detecting a difference between a control value ( ) of an allowable fuel flow that depends mainly on the engine speed, and a real flow value detected by sensors ( ).

Self-testable architecture for overspeed limitation and cutoff systems when the turbojet stops

A fuel valve for a fuel flow injection circuit, operating on electrical energy rather than hydraulic energy. The fuel valve has a valve body, a first fuel inlet opening, and a distribution assembly having a plug rotating in a bushing, the plug and bushing each having an opening slit. The valve body includes a fuel outlet opening section made by an overlapping area between the opening in the bushing and the opening in the plug. A plug position unit is provided to control a position of the plug in rotation, and the plug position unit is disposed in the valve body. The valve body further contains an electric motor that drives a rotation of a reduction gear assembly, the reduction gear assembly comprising an input shaft and an output pinion. The plug comprises a toothed sector engaging on the splines of the reduction gear assembly output pinion such that rotating the electric motor causes a rotation of the plug.

Direct control fuel valve for fuel flow injecting circuit

A main filter for an airplane fuel circuit or a fuel circuit for any type of mechanism, the filter having a first and second entry, which go directly into a chamber containing a filtering unit, the first entry receiving the fuel at a temperature essentially equal to that of the second entry which receives a hotter fuel which has passed through a heat exchanger. The filter prevents clogging due to ice formation on the filtering unit of the filter or at least inhibits such clogging. A fuel circuit using such a filter is also disclosed.

Fuel circuit with protected main filter

A self-washing device for separating and filtering solid particles from a ow of liquid includes a tubular casing defining an internal chamber, a tangential liquid inlet opening into the internal chamber and arranged to create a vortex in the internal chamber which acts to centrifuge out solid particles and carry them at the vortex periphery, a tangential liquid outlet for discharge of liquid carrying the solid particles from the internal chamber, and a tubular filter disposed longitudinally within the internal chamber for taking and filtering a portion of liquid flow at a center of the vortex, the filter having a longitudinal central duct communicating with at least one longitudinal liquid outlet for the filtered liquid. The device is of particular use in a fuel injection circuit.

Self-washing device for separating and filtering solid particles from a

An apparatus for orienting the forces exerted by a helical coil spring on relatively movable elements is disclosed in which a movable element is movably mounted within a casing so as to move along a movement axis, in which a helical coil spring is interposed between the casing and the movable element so as to exert opposite forces on the casing and the movable element. The lateral forces and the torque forces on the movable element are eliminated by using a swivel joint interposed between the piston and one end of the helical coil spring. The use of the swivel element insures that the force exerted on the movable element by the helical coil spring is coincident with the movement axis of the movable element. A second swivel joint may be utilized between the second end of the helical coil spring and the casing, if desired.

Device for orienting spring forces on relatively movable elements

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.

Device for actively controlling combustion instabilities and for

Growing community of inventors

Rubelles, France

Jean-Marie Brocard