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

Snecma

Gerard M Mandet

Pierre A Glowacki

Michel R Ayache

Marcel R Soligny

Rodolphe Martinez

Josette Benoist

Jacques H Mouchel

Michel A Desaulty

Gerard E Jourdain

Marc R Marchi

Patrice A Commaret

Didier H Hernandez

Jacques R Serre

Jean-Paul Lagrange

Jean-Claude Laugeois

Jean-Philippe E Richard

AndreA M Camboulives

The disclosed invention relates to a sealing device for the rotor blades of a gas turbine engine which permits real time adjustment to be made of the clearances between the rotor blade tips and the sealing structure. The sealing shroud around the turbine wheel is formed of sectors, each sector being attached to a monolithic short response time ring and a monolithic long response time ring. Ventilating air from upstream of the turbine wheel is directed onto the rings such that the sectors are caused to radially expand or contract in compliance with the expansion or contraction of the tips of the rotor blades during stabilized and transient engine operational modes. A small positive clearance between the sealing sectors and the blade tips is maintained throughout the range of the engine's operation.

Gas turbine engine rotor blading sealing device

The suspension of the rotor of the low pressure turbine of a twin hub turbo-engine includes a cylindrical support arranged coaxially with the axis of the turbine and firmly attached to the stator by radial spacers at the rear of the turbine, the rotor being carried on a front bearing and a rear bearing both mounted on the cylindrical support.

Low pressure turbine rotor suspension in a twin hub turbo-engine

The combustion chamber according to the present invention utilizes a double-walled structure only in the converging portion of the combustion chamber. A hot wall is retained adjacent to, but spaced from a corresponding cold wall so as to provide a cooling space between them. An upstream portion of the hot wall is retained in a notch defined by the cold wall, while the downstream portions each have generally radially extending flanges. Studs pass through openings in the adjacent flanges to prevent any relative circumferential movement, while a clamp serves to attach the flanges to the inlet of a turbine. The clamp slidably retains the flanges therein so as to permit relative radial movement to accommodate any thermal expansion and contraction of the combustion chamber, solely by the appended claims.

Turbojet engine combustion chamber with a double wall converging zone

A control mechanism for injector diaphragms in a turbojet engine is disclosed wherein an annular fairing is utilized to synchronize the movement of the individual air-fuel injector diaphragms. The fairing member is interconnected to each of the diaphragms and a single control element controls the rotational movement of the annular fairing. This minimizes the turbulence of the air flow passing around the control system.

Control mechanism for injector diaphragms

The present invention discloses a device for varying the fluid passage area between adjacent turbine stator vanes. Upstream and downstream baffles are pivotally attached to the turbine casing, such that their distal ends may be extended into and retracted from the fluid passage area, so as to vary the cross section of the throat between adjacent vanes. A control system interconnects all of the baffles so as to synchronize and positively control their movements. The invention finds particular use in an aircraft turbojet engine.

Device for varying the fluid passage area between adjacent turbine

The rotor of each stage of a turbine is surrounded, with a clearance by a fixed ring, formed by a metal ring supporting internally an annular thermal screen, in the form of ceramic segments. Expansions and contractions of the metal ring under the action of air which is supplied thereto in order to control the said clearance are transformed into displacements of radial faces of the ring in contact with radial flanges rigid with the turbine casing and seals serve to ensure fluidtightness of the ring.

Sealing ring for a turbine rotor of a turbo machine and turbo machine

The present invention concerns the cooling of turbine rotors, especially those of aircraft turboreactors, and discloses a turbine disc equipped with two sets of channels bored respectively close to each of the sides of the disc and in conformity with its profile, in which flows the cooling air of the turbine blades in order to superficially cool the disc.

Turbine rotor cooling

Jet pipe device for turbojet engines, having at least one annular assembly of flaps with variable inclinations with respect to the axis of the assembly. The device has an assembly of control elements, each of which is associated with a flap to control the inclination of this flap; a synchronizing device interconnecting all of the racking lever; and an annular support element carrying both the flaps and the control devices.

Wet pipe device for turbojet engines

The system for mounting and attaching turbine and compressor prismatic rooted blades includes a mounting sector formed by the elimination of two circumferential flanges provided on the edges of the rim. The length of the sector is about three widths of the blade platform with a stop-blade having two diametrically opposite cut corners and a four-tooth stop-comb. The corresponding mounting procedure consists of turning the stop-blade between the vanes placed in the bottom of the sector and passing its platform above those of the two adjacent blades. The comb is introduced between the platforms of the three blades and the bottom of the sector.

System for mounting and attaching turbine and compressor prismatic

A portion of the stator of a gas turbine known as turbine shroud, which is ituated radially opposite the mobile vanes of a turbine stage includes an 'abradable' member supported by a first shell braced by a second shell and connected with turbine casing 2 by a thin, i.e. flexible, annular wall member embedded in a casing. Cooling air inflates the second shell so as to brace the exterior shell and circulates between the two shells so as to cool them and also cools the 'abradable' member by impingement. The present invention is applicable to aviation turbojets.

Temperature control device for gas turbines

A labyrinth seal mounted between a shaft and the casing of a gas turbine combustion chamber, wherein the support of an abradable sealing surface in the seal which operates in conjunction with rapidly rotating fins is cooled by an upstream airflow parallel to the envelope surface of the extremities of such fins and opening into an upstream space. The cooling air is taken in from the casing by means of a conduit which is connected with an overflow valve tied to the gas turbine load. The invention is applicable to aviation turbojets.

Labyrinth seals

The rim of a turbine disc is provided with a circular collar upon which is ngaged the heel of an annular flange having a U-shaped cross section with unequal sectors, i.e., a principal piece forming a circlip and a smaller piece forming a key which completes the flange following the installation of the circlip; the key is retained in its position by cuts of the ends of said key.

Rotor flanges of turbine engines

A turbine housing for a jet engine is provided with a ring of an abradable orous material. A supporting and mounting device consisting of a cylindricoconical monoblock having a conical internal jacket provides for the convection cooling of the external surface and a cylindrical jacket for cooling air is held over the abradable ring by means of a perforated ferrule integral with the rest of the device. The abradable ring carries transverse partitions to prevent axial leakage.

Porous abradable shroud with transverse partitions

A device to secure and insure the tightness of vanes of a turbine is an alar plate which carries on the side toward its external edge a plurality of studs and toward its internal edge a plurality of hangers. The disk of the rotor has on its lower edge a series of teeth or indentations, the top of the teeth having a configuration to cooperate with the inner surface of the hangers. The vanes have on their rims a plurality of grooves. Two adjacent vanes form a groove into which the studs enter when the hangers cooperate with the teeth. The studs are borne by tongues cut radially into the annular plate.

Growing community of inventors

Epinay sous Senart, France

Gerard M Mandet