High to low pressure spool summing gearbox for accessory power extraction and electric start

• US 7,882,691 B2
• Filed: 07/05/2007
• Issued: 02/08/2011
• Est. Priority Date: 07/05/2007
• Status: Active Grant

• Current Assignee: Hamilton Sundstrand Corporation (Rtx Corporation)
• Original Assignee: Hamilton Sundstrand Corporation (Rtx Corporation)
• Inventors: Behling, David S., Lemmers, Glenn C. Jr.
• Primary Examiner(s): Rodriguez; William H
• Application Number:
  US11/773,471
• Publication Number:
  US 20090007569A1
• Time in Patent Office: 1,314 Days
• Field of Search: 607/92, 608/02, 60/391.63, 607/86, 607/88, 746/64, 746/65.R, 746/61, 746/65.L, 746/65.M, 746/65.N, 475/6, 475/9, 475/10, 475/302, 475/207, 475/218
• US Class Current: 60/39.163
• CPC Class Codes: F02C 7/275 Mechanical drives
• CPC Class Codes: F02C 7/36 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 Class Codes: F05D 2220/76 an electrical generator
• CPC Class Codes: F05D 2260/40311 of the epicyclical, planetary or differential type
• CPC Class Codes: Y10T 74/19019 Plural power paths from prime mover

Abstract

A turbine engine includes low and high pressure spools. A high power take-off shaft is coupled to the high spool. An auxiliary component, such as a generator, is configured to be driven by the high power take-off shaft at a first speed. The low spool, in part, drives the auxiliary component, for example, by interconnecting the high power take-off shaft to a lower power take-off shaft through a speed summing gearbox. The gearbox drives the auxiliary component and increases the rotational speed of the auxiliary component from the first speed to the second speed. The low power take-off shaft also drives another generator, in one example. The turbine engine can be started by the low pressure generator, for example, in response to a command from a controller, which transforms the generator into a starter motor.

Claims

1. A turbine engine comprising:

low and high pressure spools;

a high power take-off shaft coupled to the high pressure spool;

a first auxiliary component configured to be driven by the high power take-off shaft at a first speed;

a gearbox interconnecting the low pressure spool to the first auxiliary component, the gearbox configured to drive the first auxiliary component at a second speed greater than the first speed;

a low power take-off shaft coupled to the low pressure spool and a second auxiliary component configured to be driven by the low power take-off shaft;

wherein the gearbox interconnects the low and high power take-off shafts; and

wherein the gearbox includes an epicyclic gear train configured to receive a rotational input from the low power take-off shaft for increasing a rotational speed provided to the second auxiliary component.

2. The turbine engine according to claim 1, wherein the epicyclic gear train includes a ring gear driven by the low power take-off shaft, the ring gear providing rotational input to planetary gears supported by a carrier, the carrier coupled to the high power take-off shaft, and a sun gear receiving rotational drive from the planetary gears, the sun gear providing rotational input to the second auxiliary component.

3. The turbine engine according to claim 2, wherein the high power take-off shaft supports a gear for transmitting additional speed from the gearbox to the high power take-off shaft.

4. The turbine engine according to claim 3, comprising an idler gear interconnecting the gear and a driven gear supported by the carrier.

5. The turbine engine according to claim 3, comprising a third auxiliary component interconnecting the gear and a driven gear supported by the carrier.

6. The turbine engine according to claim 5, wherein the third auxiliary component is a hydromechanical generator.

7. The turbine engine according to claim 1, wherein the first auxiliary component is a first generator.

8. The turbine engine according to claim 1, wherein the second auxiliary component is a second generator.

9. The turbine engine according to claim 8, comprising a controller providing a command to the second generator for selectively rotating the high pressure spool through the gearbox with the second generator in a start procedure.