Snecma Moteurs

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

Hispano Suiza

Snecma

Alain Tiepel

Marion Michau

Jos&eacute; Rodrigues

Guy D'Agostino

Jean-Marie Brocard

Claude M Maillard

Pierre G Hebert

Alain Lavie

José Roland Rodrigues

St&eacute;phanie Martelli

Eric C Lorne

Franck Liotte

Denis J Sandelis

Didier Georges Feder

Gw&eacute;na&euml;lle Calvez

Jose Roland Rodrigues

Pascal Marly

Christophe Viguier

Michel Hugues

Pascal LeBlanc

Severine Chevalier

Guv d'Agostino

Alain Schuler

Fr&eacute;d&eacute;ric Ravet

Etienne David

Stephanie Martelli

Frederic Ravet

Gwenaelle Calvez

The present invention relates to a method for differentiating control failures in a system for controlling an actuator () determining the position of a member for modifying the state of a gas-turbine engine, the system including a single- or dual-channel electric control and a mechanical control, the electric control including one computer (') per channel, only one of which is active at any given time in order to calculate the set position of the movable member of the actuator () and to transmit a set signal to the single-channel mechanical control of the actuator, a failure being diagnosed when a deviation is detected between the set position of the movable member of the actuator and the position thereof measured during a predetermined deviation confirmation time. The method is characterised in that the speed of movement of the actuator is measured and in that the system diagnoses an electrical failure when, during said time for confirming the deviation, the measured speed of movement is other than zero and remains higher than a predetermined threshold speed; otherwise, the failure is diagnosed as being of temporary mechanical origin.

Method for differentiating control failures in a system for controlling an actuator, in particular of a stator of a gas-turbine engine

This injector with two valves () which open at different fuel pressures so as to establish a primary flow regime and then a secondary flow regime is characterized in that the primary regime is enriched with fuel via an orifice () which adds a branch to the primary flow path of the fuel, but which is closed when the secondary valve is displaced so as to prevent enrichment of the fuel in the secondary regime. This invention applies in particular to certain aircraft engines.

Two-stage fuel injector

A fluid metering device including a metering valve capable of sliding in a bushing under fluid feed pressure in order to enable a fluid to be admitted and then ejected. The valve can have, at a first end, an opening opening out into a longitudinal fluid admission bore, and at a second end forming an end wall, a valve head provided with fluid metering slots opening out into the longitudinal bore and defining varying flow sections. The valve head can further include at least one substantially transverse orifice disposed downstream from the metering slots in the fluid flow direction, the orifice communicating with the longitudinal bore and defining at least one fixed flow section.

Fuel metering device for a turbomachine injector

A system for injecting fuel into a turbomachine comprising N fuel injectors placed in a combustion chamber of the turbomachine and fed from a fuel tank, the injection system further comprising, interposed between the N injectors and the tank, a single pumping means for taking fuel from the tank and delivering N metered flow rates of fuel to the injectors.

System for injecting fuel into a turbomachine

A system for injecting an air/fuel mixture into a combustion chamber of a turbomachine, the system having an injector comprising: an axial internal volume opening out at one end via an axial outlet for the air/fuel mixture; a first fuel feed stage having a plurality of first fuel feed orifices which open out into the internal volume, which are distributed around an axis of the injector, and which are connected by fuel feed channels to an inlet for admitting fuel into the injector; and at least one air feed channel which opens out into the internal volume and which is connected to an inlet for admitting air into the injector. The injector further comprises at least one second fuel feed stage with a plurality of second fuel feed orifices which open out into the internal volume, which are distributed around the axis of the injector, and which are connected to said inlet for admitting fuel into the injector via fuel feed channels which coincide at least in part with the fuel feed channels of said first stage.

Fuel injection system with multipoint feed

The invention provides an injection system for injecting an air/fuel mixture into a combustion chamber of a gas turbine engine, the injection system having a longitudinal axis and comprising fuel injection means, interposed between first and second air injection means, the fuel injection means being disposed in an annular internal cavity of a Venturi, the fuel injection means comprising at least a first fuel admission circuit provided with at least one fuel injection orifice, and a plurality of second fuel admission circuits independent from the first fuel admission circuit(s), each being provided with at least one fuel injection orifice so as to define a plurality of independent modes of injecting the air/fuel mixture depending on determined operating speeds of the engine, the fuel injection orifice of the first fuel admission circuit being formed in the upstream wall of the Venturi so as to inject fuel towards the combustion chamber in a general direction that is substantially perpendicular to a flow of air coming from the first air injection means, and the fuel injection orifices of the second fuel admission circuits being formed in the downstream wall of the Venturi so as to inject fuel towards the combustion chamber in a general direction that is substantially perpendicular to a flow of air coming from the second air injection means.

Multimode system for injecting an air/fuel mixture into a combustion chamber

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&deg; all the way to the end of the injector.

Full cooling of main injectors in a two-headed combustion chamber

A fuel injector for a turbomachine engine, the injector comprising an injector body having pressurized fuel admission means, a first valve mounted downstream from the pressurized fuel admission means and arranged to admit fuel into the injector body, a second valve mounted downstream from the first valve and capable of opening in order to meter at least a fraction of the fuel admitted into the injector body for utilization means for using the fuel, the metered fuel flow rate to the utilization means being a function of flow sections formed through the second valve, the injector further comprising a diaphragm placed between the pressurized fuel admission means and the first valve so as to set the rate at which fuel is admitted into the injector body at a determined value.

Turbomachine injectors

A fuel injector has a metering valve arranged to open under a predetermined feed pressure which constitutes a first threshold pressure, and to remain open in response to said feed pressure increasing so as to deliver fuel to fuel utilization means. The flow rate of fuel passing through the injector is metered to feed said utilization means so long as the feed pressure remains below a second threshold pressure greater than the first threshold pressure. Above the second threshold pressure, the metering valve behaves like a fixed diaphragm as a function of the fluid flow sections formed therethrough. Individual adjustment means are provided so as to enable said second threshold pressure to be adjusted for each injector to ensure that fuel is injected at a uniform flow rate by all of the injectors in a combustion chamber.

Fuel injector with an optimized metering device

An assembly method in which a brazing metal is initially filled into radial wells pierced in an annular injection piece having first injection orifices for discharging a primary fuel, and in a cylindrical endpiece surrounding the annular injection piece and having secondary injection orifices for discharging a secondary fuel; thereafter the annular injection piece is fitted inside the cylindrical endpiece and these pieces are together fitted on a first tube for feeding primary fuel and a second tube for feeding secondary fuel and surrounding the first tube, and also to an outer wall of the injector; finally, the end portion of the injector as assembled in this way is placed in an enclosure where it is heated so as to melt the brazing metal to unite the parts.

Method of assembling a fuel injector for the combustion chamber of a turbomachine

In a fluid metering device for metering a fluid from a supply source to means of use of this fluid comprising a metering valve able to slide in a sleeve over a travel C, this valve comprising an intake orifice ( ) for admitting the fluid from the said supply source and an orifice ( ) for ejecting this fluid to the means of use, there are provided means ( ) for channelling the fluid intended to allow, during the movement of the metering valve in its sleeve, a sweeping of the fluid over all the contacting surfaces of the valve and of the sleeve. The means of channelling the fluid advantageously comprise a helical groove of width L and of pitch P.

Self-cleaning metering device

A rotary valve assembly is disclosed in which a rotary valve member is located within a casing having one or more fluid inlets and a plurality of fluid outlets. The rotary valve member has a fluid conduit which extends in a generally radial direction and which communicates with the fluid inlet. Fluid orifices communicate with the fluid conduit and exit through opposite sides of the rotary valve member to thereby minimize, or eliminate altogether, axial forces acting on the rotary valve member. Fluid outlet passages communicate with the two fluid orifices during at least pan of the rotation of the rotary valve member to direct the pressurized fluid to the valve outlets. The rotary valve may include a pair of rotary valve members drivingly connected to each other such that they rotate synchronously. The connection may include gear teeth formed on the adjacent peripheries of the rotary valve members such that rotation of one of the valve members causes rotation of the other. Each valve member may have a separate fluid inlet and separate fluid outlets.

Rotary valve assembly

A rotary valve assembly is disclosed in which a rotary valve member is located within a casing having one or more fluid inlets and a plurality of fluid outlets. The rotary valve member has a fluid conduit which extends in a generally radial direction and which communicates with the fluid inlet. Fluid orifices communicate with the fluid conduit and exit through opposite sides of the rotary valve member to thereby minimize, or eliminate altogether, axial forces acting on the rotary valve member. Fluid outlet passages communicate with the two fluid orifices during at least part of the rotation of the rotary valve member to direct the pressurized fluid to the valve outlets. The rotary valve may include a pair of rotary valve members drivingly connected to each other such that they rotate synchronously. The connection may include gear teeth formed on the adjacent peripheries of the rotary valve members such that rotation of one of the valve members causes rotation of the other. Each valve member may have a separate fluid inlet and separate fluid outlets.

A ball-type sealing device is disclosed for preventing fluid flow out of an orifice wherein the sealing ball is mounted in a body member so as to have both radial or transverse and axial degrees of freedom. The sealing ball, which has a diameter greater than that of the orifice, is mounted in a chamber defined by the body member such that a portion of the ball extends through an aperture in the end of the chamber to the exterior of the body member. The sealing ball is positioned by a pushrod slidably extending into an elongated hole defined by the body member such that one end of the pushrod, having a first contact surface S.sub.1, is in contact with the sealing ball. The opposite end of the pushrod is associated with a second contact surface S.sub.2 which has an area smaller than the contact surface S.sub.1. The sealing ball may be accurately placed in the orifice to be sealed since it has both a transverse degree of freedom, due to the diameter of the chamber in the body member being larger than the diameter of the sealing ball, as well as an axial degree of freedom. Pressure exerted on the sealing ball along the longitudinal axis of the body member exerts a force on the pushrod which, in turn, causes permanent axial deformation of a crush portion of the body member adjacent to the second end of the pushrod. This deformation provides the necessary axial play or clearance between the pushor and the ball.

Growing community of inventors

Chailly en Biere, France

Alain Tiepel