Rotor for jet engines

• US 4,277,225 A
• Filed: 09/20/1978
• Issued: 07/07/1981
• Est. Priority Date: 09/23/1977
• Status: Expired due to Term

• Current Assignee: Societe Nationale dEtude et de Construction de Moteurs dAviation SNECMA (Safran SA)
• Original Assignee: Societe Nationale dEtude et de Construction de Moteurs dAviation SNECMA (Safran SA)
• Inventors: Surdi, Jean M., Dubois, Claude
• Primary Examiner(s): Powell, Jr., Everette A.
• Application Number:
  US05/944,205
• Time in Patent Office: 1,021 Days
• Field of Search: 416/198 A, 416/193 A, 416/201 R, 416/219 R, 416/221, 415/199.5
• US Class Current: 416/198.00A
• CPC Class Codes: F01D 11/001 for sealing space between stator blade and rotor
• CPC Class Codes: F01D 5/06 Rotors for more than one axial stage, e.g. of drum or multiple disc type; Details thereof, e.g. shafts, shaft connections F01D5/022, F01D5/023 take precedence
• CPC Class Codes: F01D 5/3007 of axial insertion type
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A rotor for jet engines includes a drum formed by disks and carrying blad Between the blades of two adjacent stages, braces are interspaced, the braces being projections which engage in sockets provided for this purpose on the disks. Each disk has two series of sockets, one receiving the roots of the blades, and the other, interspaced between the preceding, the projections of the braces. The blades are immobilized in translation at the upstream end by one ring and downstream by another ring, against which the roots of the blades of the terminal stages abut. The invention is particularly applicable to the building of axial type compressor rotors having several stages.

Claims

1. An axial type rotor for jet engines, particularly for compressors, having an alternating stack of disks and of annular elements having external diameters smaller than those of said disks so as to provide spaces for stationary blades, each stage of said rotor comprising a number of identical blades, characterized in that in each disk two series, each comprising uniformly distributed axial grooves equal in number to that of the blades, are arranged, the grooves of a first series being aligned from one end of the rotor to the other, with the grooves of said first series having a configuration adapted to receive a root of a blade, the grooves of the second series, interspaced between those of said first series and having a configuration adapted to receive identical projections of braces equal in number to that of the blades, said projections insuring the axial immobilization of the blades by means of a platform carried by said braces and abutting said blades, the configuration of the grooves of the first and second series being such that said grooves cooperate respectively with the roots of the blades and the projections of the braces, to assure a joint impeding of all radial motion with respect to the rotor of the blades and of the braces.

2. A rotor according to the preceding claim, characterized in that the width, measured in the axial direction, of each disk is essentially equal to the axially measured length of a root of a blade.

3. A rotor according to any one of the preceding claims, characterized in that each brace consists of a platform of an axial length corresponding to the space separating two blade-carrying disks, said platform extending circumferentially in a symmetrical fashion and with the platforms of adjacent braces cooperating so as to form an annular surface virtually continuous, once the braces are set in place, and of two aligned projections extending axially past the platform into the grooves of the second series of two adjacent blade carrying disks.

4. A rotor according to claim 3, characterized in that the platforms of the braces carry sealing devices for cooperation with the inner ends of stationary blades.

5. A rotor according to claim 3, characterized in that the braces are made of a material having a density lower than the material used for the rotor.

6. A rotor according to claim 3, characterized in that the configurations of the grooves of the first and second series are identical, the shapes of the roots of the blades and of the projections of the braces also being identical.

7. A rotor according to claim 3, characterized in that the locking in place of the blade assembly, once installed, is provided by means of a first ring forming a stop at the upstream face of the roots of the blades of the upstream stage and a second ring forming a stop at the downstream face of the roots of the blades of the downstream stage, the two rings being secured to the rotor so that at least one of them is removable.