Turbofan engine bearing and gearbox arrangement

Patent metadata

Field	Value
Publication number	US-10094278-B2
Application number	US-201414892103-A
Country	US
Kind code	B2
Filing date	May 6, 2014
Priority date	Jun 3, 2013
Publication date	Oct 9, 2018
Grant date	Oct 9, 2018

Abstract

A turbofan engine ( 20 ) comprises a fan ( 28 ). A fan drive gear system ( 60 ) is configured to drive the fan. A low spool comprises a low pressure turbine ( 50 ) and a low shaft ( 56 ) coupling the low pressure turbine to the fan drive gear system. An intermediate spool comprises an intermediate pressure turbine ( 48 ), a compressor ( 42 ), and an intermediate spool shaft ( 54 ) coupling the intermediate pressure turbine to the intermediate spool compressor. A combustor ( 45 ) is between a core spool compressor ( 44 ) and a high pressure turbine ( 46 ). A first ( 160 ) main bearing engages a static support ( 164; 164 ′) and a forward hub ( 236 ) of the intermediate spool. A second ( 162 ) main bearing engages the low shaft and the forward hub.

First claim

What is claimed is:

1. A turbofan engine ( 20 ) comprising:
a single-stage fan ( 28 );
a fan drive gear system ( 60 ) configured to drive the fan;
a low spool comprising:
a low pressure turbine ( 50 ); and
a low shaft ( 56 ) coupling the low pressure turbine to the fan drive gear system;

an intermediate spool comprising;
an intermediate pressure turbine ( 48 );
a compressor ( 42 ); and
an intermediate spool shaft ( 54 ) coupling the intermediate pressure turbine to the intermediate spool compressor;

a core spool comprising:
a high pressure turbine ( 46 );
a compressor ( 44 ); and
a core shaft ( 52 ) coupling the high pressure turbine to the core spool compressor;

a combustor ( 45 ) between the core spool compressor and the high pressure turbine; and
a plurality of main bearings,

wherein:
the fan drive gear system comprises:
a sun gear ( 80 ) mounted to rotate with the low shaft;
a ring gear ( 82 ) mounted to rotate with the fan;
a plurality of intermediate gears ( 84 ) between the sun gear and the ring gear; and
a carrier ( 86 ) holding the intermediate gears;

a first ( 160 ) of said plurality of main bearings engages a static support ( 164 ; 164 ′) and a forward hub ( 236 ) of the intermediate spool; and
a second ( 162 ) of said plurality of main bearings engages the low shaft and the forward hub of the intermediate spool.

2. The engine of claim 1 wherein:
the forward hub extends forward from a disk of the intermediate spool compressor.

3. The engine of claim 2 wherein:
the forward hub extends forward from a bore ( 237 ) of the disk of the intermediate spool compressor.

4. The engine of claim 2 wherein:
the intermediate spool compressor has at least one disk forward of said disk.

5. The engine of claim 4 wherein:
the static support ( 164 ′) passes through said at least one disk forward of said disk.

6. The engine of claim 4 wherein:
the intermediate spool compressor has at least two disks forward of said disk.

7. The engine of claim 4 wherein:
said at least one disk is forward of a centerplane ( 526 ) of the second bearing.

8. The engine of claim 1 wherein:
a separation of a transverse centerplane ( 524 ) of the first bearing and a transverse centerplane ( 526 ) of the second bearing is less than a radius (R B ) of the first bearing.

9. The engine of claim 1 wherein:
a first seal ( 290 ) seals the first bearing and a second seal ( 292 ) seals the second bearing to isolate a transmission compartment ( 286 ) ahead of the first bearing and the second bearing from a region ( 288 ) behind the first bearing and the second bearing.

10. The engine of claim 1 wherein:
a third of said plurality of main bearings is a thrust bearing ( 170 ) engaging the low shaft.

11. The engine of claim 10 wherein:
a fourth of said plurality of main bearings is a non-thrust roller bearings bearing ( 172 ) engaging an aft end of the low shaft.

12. The engine of claim 1 wherein:
the core shaft engages at least two of said plurality of main bearings, and wherein at least one of said at least two of said main bearings is a thrust bearing.

13. The engine of claim 1 wherein:
the low pressure turbine has three to five blade stages.

14. The engine of claim 1 wherein:
the intermediate spool shaft engages at least two of said plurality of main bearings, and wherein at least one of said at least two of said main bearings is a thrust bearing.

15. The engine of claim 1 wherein:
an inter-shaft bearing ( 170 ) axially locates the low shaft.

16. The engine of claim 1 wherein:
the low shaft engages at least three of said plurality of main bearings.

17. A turbofan engine ( 20 ) comprising:
a fan ( 28 );
a fan drive gear system ( 60 ) configured to drive the fan;
a low spool comprising:
a low pressure turbine ( 50 ); and
a low shaft ( 56 ) coupling the low pressure turbine to the fan drive gear system;

an intermediate spool comprising;
an intermediate pressure turbine ( 48 );
a compressor ( 42 ); and
an intermediate spool shaft ( 54 ) coupling the intermediate pressure turbine to the intermediate spool compressor;

a core spool comprising:
a high pressure turbine ( 46 );
a compressor ( 44 ); and
a core shaft ( 52 ) coupling the high pressure turbine to the core shaft;

a combustor ( 45 ) between the core spool compressor and the high pressure turbine; and
a plurality of main bearings wherein:
a first ( 160 ) of said main bearings engages a static support ( 164 ; 164 ′) and a forward hub ( 236 ) of the intermediate spool; and
a second ( 162 ) of said main bearings engages the low shaft and the forward hub of the intermediate spool;
the first bearing and the second bearing are non-thrust roller bearings; and
rollers of the first bearing and the second bearing are at least partially longitudinally overlapping.

18. The engine of claim 17 wherein:
a first seal ( 290 ) seals the first bearing and a second seal ( 292 ) seals the second bearing to isolate a transmission compartment ( 286 ) ahead of the first bearing and the second bearing from a region ( 288 ) behind the first bearing and the second bearing.

19. A turbofan engine ( 20 ) comprising:
a fan ( 28 );
a fan drive gear system ( 60 ) configured to drive the fan;
a low spool comprising:
a low pressure turbine ( 50 ); and
a low shaft ( 56 ) coupling the low pressure turbine to the fan drive gear system;

an intermediate spool comprising;
an intermediate pressure turbine ( 48 );
a compressor ( 42 ); and
an intermediate spool shaft ( 54 ) coupling the intermediate pressure turbine to the intermediate spool compressor;

a core spool comprising:
a high pressure turbine ( 46 );
a compressor ( 44 ); and
a core shaft ( 52 ) coupling the high pressure turbine to the core spool compressor;

a combustor ( 45 ) between the core spool compressor and the high pressure turbine; and
a plurality of main bearings wherein:
a first ( 160 ) of said plurality of main bearings engages a static support ( 164 ; 164 ′) and a forward hub ( 236 ) of the intermediate spool;
a second ( 162 ) of said plurality of main bearings engages the low shaft and the forward hub of the intermediate spool; and
an inter-shaft bearing ( 170 ) of said plurality of main bearings axially locates the low shaft.

20. The engine of claim 19 wherein:
a first seal ( 290 ) seals the first bearing and a second seal ( 292 ) seals the second bearing to isolate a transmission compartment ( 286 ) ahead of the first bearing and the second bearing from a region ( 288 ) behind the first bearing and the second bearing.

Assignees

• United Technologies Corp

Inventors

• Sheridan William G
• Schwarz Frederick M
• Suciu Gabriel L

Classifications

• F05D2240/24

  for turbines · CPC title

• F02C7/36

  Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user ({F02C3/107 - F02C3/13 and} F02C7/32 take precedence; couplings for transmitting rotation F16D; gearing in general F16H) · CPC title

• F16C19/545

  Systems comprising at least one rolling bearing for radial load in combination with at least one rolling bearing for axial load · CPC title

• F05D2240/35

  Combustors or associated equipment · CPC title

• F01D25/162

  Bearing supports · CPC title