Off-axis electric actuation for variable vanes

• US 10,288,087 B2
• Filed: 03/24/2016
• Issued: 05/14/2019
• Est. Priority Date: 03/24/2016
• Status: Active Grant

• Current Assignee: Rtx Corporation
• Original Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Suciu, Gabriel L, Chandler, Jesse M
• Primary Examiner(s): Seabe, Justin
• Assistant Examiner(s): Haghighian, Behnoush
• Application Number:
  US15/079,446
• Publication Number:
  US 20170276148A1
• Time in Patent Office: 1,146 Days
• CPC Class Codes: F01D 17/12 arranged in stator parts
• CPC Class Codes: F01D 17/14 varying effective cross-sectional area of nozzles or guide conduits
• CPC Class Codes: F01D 17/162 for axial flow, i.e. the vanes turning around axes which are essentially perpendicular to the rotor centre line F01D17/167 takes precedence
• CPC Class Codes: F01D 17/165 for radial flow, i.e. the vanes turning around axes which are essentially parallel to the rotor centre line F01D17/167 takes precedence
• CPC Class Codes: F01D 7/00 Rotors with blades adjustable in operation; Control thereof for reversing F01D1/30
• CPC Class Codes: F01D 9/04 forming ring or sector
• CPC Class Codes: F01D 9/042 fixing blades to stators fixing stator-rings in the casing or to each other F01D25/246
• CPC Class Codes: F02B 37/24 by using pumps or turbines with adjustable guide vanes
• CPC Class Codes: F04D 29/323 adjustable
• CPC Class Codes: F04D 29/542 Bladed diffusers fixing blades to stators F01D9/042
• CPC Class Codes: F04D 29/563 specially adapted for elastic fluid pumps
• CPC Class Codes: F05D 2220/32 in gas turbines
• CPC Class Codes: F05D 2270/62 Electrical actuators
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A variable vane system for a gas turbine engine, comprising an actuator, a harmonic drive comprising a strain wave gearing mechanism comprising a fixed circular spline, a flex spline attached to an output shaft, and a wave generator attached to an input shaft driven by the actuator, the flex spline driven by the wave generator with respect to the circular spline, a drive gear driven by the output shaft along a first axis, and an actuator gear mounted to one of a multiple of variable vanes along a second axis transverse to the first axis, the actuator gear driven by the drive gear.

Claims

1. A variable vane system for a gas turbine engine, comprising:

an actuator;

a harmonic drive comprising a strain wave gearing mechanism comprising a fixed circular spline, a flex spline attached to an output shaft, and a wave generator attached to an input shaft driven by the actuator, the flex spline driven by the wave generator with respect to the circular spline;

a drive gear driven by the output shaft along a first axis; and

an actuator gear mounted to one of a multiple of variable vanes along a second axis transverse to the first axis, the actuator gear driven by the drive gear;

a unison ring driven by the drive gear, a link between each variable vane and the unison ring such that the multiple of variable vanes are driven by the unison ring.

2. The system as recited in claim 1, wherein the harmonic drive is operable to direct drive the one of the multiple of variable vanes via the actuator gear.

3. The system as recited in claim 1, wherein the harmonic drive provides between a 30:

1-320;

1 gear ratio.

4. The system as recited in claim 1, wherein the actuator gear is a gear segment.

5. The system as recited in claim 4, wherein the actuator gear is operable to rotate through 90 degrees.

6. The system as recited in claim 4, wherein the actuator gear is operable to rotate through 0-40 degrees.

7. The system as recited in claim 1, wherein the actuator gear is mounted to a trunion of one of the multiple of variable vanes.

8. The system as recited in claim 7, wherein the actuator gear is mounted to the unison ring.

9. The system as recited in claim 1, wherein the actuator is an electric motor.

14. The system as recited in claim 1, wherein the first axis is parallel with an engine axis.

15. The system as recited in claim 1, wherein the first axis is perpendicular to the second axis.

10. A gas turbine engine, comprising:

a harmonic drive operable to drive a multiple of variable vanes through a geared connection comprising a drive gear arranged along a first axis parallel to an engine axis, and an actuator gear mounted along a second axis transverse to the first axis, the actuator gear driven by the drive gear to rotate the multiple of variable vanes,

a unison ring driven by the drive gear, a link between each variable vane and the unison ring such that the multiple of variable vanes are driven by the unison ring.

11. The gas turbine engine as recited in claim 10, further comprising an electric motor operable to drive the harmonic drive.

12. The gas turbine engine as recited in claim 10, wherein the actuator gear is transverse to the drive gear.

13. The gas turbine engine as recited in claim 10, wherein the harmonic drive is displaced from a structural wall of the gas turbine engine.

16. The gas turbine engine as recited in claim 10, wherein the harmonic drive comprises a strain wave gearing mechanism comprising a fixed circular spline, a flex spline attached to an output shaft, and a wave generator attached to an input shaft driven by the actuator, the flex spline driven by the wave generator with respect to the circular spline.