Snecma Moteurs

Hispano Suiza

Alain Lavie

Marion Michau

Alain Tiepel

Jos&eacute; Rodrigues

St&eacute;phanie Martelli

Jean-Marie Brocard

Daniel Germain Kettler

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 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 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.

Growing community of inventors

Yerres, France

Alain Lavie