Turbojet having an electricity generator arranged in its fan

• US 7,952,244 B2
• Filed: 10/07/2008
• Issued: 05/31/2011
• Est. Priority Date: 10/08/2007
• Status: Active Grant

• Current Assignee: Safran Aircraft Engine Company
• Original Assignee: Snecma (Safran SA)
• Inventors: Colin, Antoine
• Primary Examiner(s): Mullins; Burton
• Assistant Examiner(s): Kenerly; Terrance
• Application Number:
  US12/246,604
• Publication Number:
  US 20090115295A1
• Time in Patent Office: 966 Days
• Field of Search: 290/52, 290/54, 310/67.R, 310/52, 310/54, 701/100, 415/10, 415/144
• US Class Current: 310/67.00R
• CPC Class Codes: F01D 15/10 Adaptations for driving, or combinations with, electric generators
• CPC Class Codes: F02K 3/06 with front fan
• CPC Class Codes: F05D 2220/76 an electrical generator
• CPC Class Codes: F05D 2220/764 of the alternating current (A.C.) type
• CPC Class Codes: F05D 2220/766 via a direct connection, i.e. a gearless transmission
• CPC Class Codes: F05D 2220/768 equipped with permanent magnets
• CPC Class Codes: H02K 21/14 with magnets rotating within the armatures
• CPC Class Codes: H02K 7/1823 structurally associated with turbines or similar engines

Abstract

The turbojet comprises a high pressure spool and a low pressure spool driving a fan. In order to produce electricity, it further includes an electricity generator arranged in the fan and taking power therefrom. The generator comprises a rotor incorporated in the fan and a stator incorporated in the fan casing. This disposition for the electricity generator avoids problems of engine operability at low speed and enables mechanical power to be converted into electrical power with high efficiency. In addition, installation and maintenance of the electricity generator are facilitated by the generator being implanted in the fan.

Claims

1. A turbojet comprising:

a high pressure spool;

a low pressure spool driving a fan disposed in a stationary casing; and

an electricity generator arranged in the fan, taking power therefrom, the electricity generator including a rotor incorporated in the fan and a stator incorporated in the fan casing, the rotor including permanent magnets fastened to blades of the fan and the stator including windings,

wherein the windings are provided inside a scoop disposed inside the fan casing,

wherein a cooling tube in fluid communication with cool air admitted into an engine nacelle casing is disposed at an outer surface of the scoop to cool the windings, and

wherein a radial gap is provided between an inner surface of the scoop and tips of the fan blades.

2. A turbojet according to claim 1, wherein the permanent magnets are fastened to the tips of the fan blades.

3. A turbojet according to claim 2, wherein said magnets are fastened by adhesive.

4. A turbojet according to claim 1, further including another generator and/or starter respectively taking or delivering power to the high pressure spool.

5. A turbojet according to claim 1, wherein the stator has exactly three windings.

6. A turbojet according to claim 1, wherein said electricity generator further includes an AC/DC converter.

7. A turbojet comprising:

a fan disposed in a stationary casing;

a high pressure spool comprising a high pressure compressor and a high pressure turbine;

a low pressure spool comprising a low pressure compressor and a low pressure turbine and driving said fan; and

an electricity generator arranged in the fan, taking power from said fan, the electricity generator including a rotor incorporated in the fan and a stator incorporated in the fan casing, the rotor including permanent magnets fastened to blades of the fan and the stator including windings,

wherein the windings are provided inside a scoop disposed inside the fan casing,

wherein a cooling tube in fluid communication with cool air admitted into an engine nacelle casing is disposed at an outer surface of the scoop to cool the windings, and

wherein a radial gap is provided between an inner surface of the scoop and tips of the fan blades.

8. A turbojet according to claim 7, wherein the permanent magnets are fastened to the tips of the fan blades.

9. A turbojet according to claim 7, wherein said magnets are fastened by adhesive.

10. A turbojet according to claim 7, further including another generator and/or starter respectively taking or delivering power to the high pressure spool.

11. A turbojet according to claim 7, wherein the stator has exactly three windings.

12. A turbojet according to claim 7, wherein said electricity generator further includes an AC/DC converter.

13. A turbojet according to claim 7, wherein the high pressure spool and the low pressure spool are configured to generate sufficient thrust for flying an aircraft.

14. A turbojet according to claim 7, wherein the rotor comprises rotor blades, wherein each rotor blade of at least a first plurality of said rotor blades includes a magnet fastened to an end of said rotor blade.

15. A turbojet according to claim 14, wherein each rotor blade of a second plurality of said rotor blades is free of any magnet.

16. A turbojet according to claim 14, wherein each of said rotor blades of said first plurality includes a root portion, said root portion being free of any magnet.

17. A turbojet according to claim 7, the engine nacelle casing houses said fan, said high pressure spool and said low pressure spool.

18. A turbojet according to claim 17, wherein said fan casing forms a part of said nacelle.