Actuation mechanism for a convertible gas turbine propulsion system

• US 8,061,119 B2
• Filed: 11/29/2007
• Issued: 11/22/2011
• Est. Priority Date: 11/29/2007
• Status: Active Grant

• Current Assignee: Rtx Corporation
• Original Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Reinhardt, Gregory E., Agrawal, Rajendra K.
• Primary Examiner(s): Rodriguez; William
• Assistant Examiner(s): SUNG, GERALD LUTHER
• Application Number:
  US11/998,248
• Publication Number:
  US 20090140182A1
• Time in Patent Office: 1,454 Days
• Field of Search: 602/28, 602/29, 602/30, 602/32, 602/263, 602/261, 602/25, 602/44, 607/91, 607/82, 607/85, 137/872, 137/874, 251/63.5, 251/5, 244/6, 244/7.R, 244/7.A, 244/7.B, 244/17.13, 244/17.19, 244/17.21
• US Class Current: 60/232
• CPC Class Codes: B64C 27/22 Compound rotorcraft, i.e. aircraft using in flight the features of both aeroplane and rotorcraft
• CPC Class Codes: B64D 33/04 of exhaust outlets or jet pipes exhaust outlets for combustion engines in general F01N; jet pipes or nozzles for jet-propulsion plants per se F02K; plants characterised by the form or arrangement of the jet pipe or nozzle F02K ; attitude, flight direction, or altitude control by jet reaction B64C
• CPC Class Codes: B64D 35/02 specially adapted for specific power plants
• CPC Class Codes: F02C 3/10 with another turbine driving an output shaft but not driving the compressor
• CPC Class Codes: F02C 6/08 the gas being bled from the gas-turbine compressor
• CPC Class Codes: F02C 6/206 the vehicles being airscrew driven
• 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: F02C 9/18 by bleeding, bypassing or acting on variable working fluid interconnections between turbines or compressors or their stages F02C3/113 takes precedence
• CPC Class Codes: F02K 1/08 by axially moving or transversely deforming an internal member, e.g. the exhaust cone
• CPC Class Codes: F02K 3/025 the by-pass flow being at least partly used to create an independent thrust component
• CPC Class Codes: F05D 2220/329 in helicopters

Abstract

An actuation mechanism for use in a convertible gas turbine propulsion system comprises a plenum, a pneumatically powered drive body and a spring system. The plenum receives pressurized air from the convertible gas turbine propulsion system. The pneumatically powered drive body is connected to the plenum to receive pressurized air to axially move the drive body in a first direction. The spring system is connected to the drive body to axially move the drive body in a second direction.

Claims

1. An actuation mechanism for use in a convertible gas turbine propulsion system, the actuation mechanism comprising:

a plenum for receiving pressurized air from the convertible gas turbine propulsion system;

a pneumatically powered drive body connected to the plenum to receive pressurized air for axially moving the drive body in a first direction;

a cowling comprising;

an annular compartment for receiving the pneumatically powered drive body; and

a port for receiving pressurized air from the plenum; and

a spring system connected to the drive body for axially moving the drive body in a second direction;

wherein the pneumatically powered drive body comprises;

an elongate main body disposed within the annular compartment;

a tail disposed at an aft end of the elongate main body configured for connecting with the spring system; and

a leaf spring for retaining the elongate main body within the annular compartment and for sealing the pressurized air within the annular compartment such that pressurized air from the plenum biases the elongate main body in the first direction.

2. The actuation mechanism of claim 1 wherein the spring system comprises:

a canister connected to an aft end of the cowling;

a piston rod extending through the canister and into the annular compartment, the piston rod comprising;

a forward end connected to the tail; and

an aft end connected to a piston head; and

a spring disposed within the canister between the piston head and the annular compartment to bias the elongate main body in the second direction.

3. The actuation mechanism of claim 2 and further comprising a spacer disposed within the canister between the spring and the annular compartment to adjust a stroke length of the piston rod.

4. The actuation mechanism of claim 2 and further comprising a cooling air manifold disposed within the cowling to deliver cooling air to the pneumatically powered drive body.

5. The actuation mechanism of claim 2 wherein the cowling includes an inner diameter surface connected with a stator vane.

6. The actuation mechanism of claim 2 wherein the elongate main body further includes a head configured as a seal such that the elongate main body extends from the annular compartment to close off a pressure chamber within the convertible gas turbine propulsion system.

7. The actuation mechanism of claim 1 and further comprising a bleed air system comprising:

conduit for delivering air compressed in a compressor section of the convertible gas turbine propulsion system to the plenum; and

a valve interconnected with the conduit for regulating pressure of the plenum.

8. An exhaust duct actuation mechanism for a convertible gas turbine propulsion system, the actuation mechanism comprising:

a retractable port comprising a forward end and an aft end;

a mechanical actuation system connected to the aft end to bias the retractable port in a first direction;

a pneumatic actuation system connected to the retractable port forward of the aft end to bias the retractable port in a second direction and;

an outer exhaust duct concentrically disposed about the retractable port, the outer exhaust duct comprising;

an aft end disposed about the aft end of the retractable port to form a bypass passage between the outer exhaust duct and the retractable port; and

a forward end axially aligned with the forward end of the retractable port such that the retractable port is axially translatable to close off the bypass passage.

9. The actuation mechanism of claim 8 and further comprising:

an aft exhaust duct aligned with the aft end of the outer exhaust duct;

an inner flow duct having a compartment for receiving the retractable port; and

a plurality of exit guide vanes connecting the aft exhaust duct with the inner flow duct.

10. The actuation mechanism of claim 9 wherein the mechanical actuation mechanism comprises:

a canister connected to the aft end of the inner flow duct;

a push rod disposed within the canister and configured for engaging the retractable port; and

a spring disposed within the canister to bias the push rod in the first direction.

11. The actuation mechanism of claim 9 wherein the pneumatic actuation mechanism further comprises:

a plenum for receiving pressurized air from the convertible gas turbine propulsion system;

conduit for delivering air compressed in a compressor section of the convertible gas turbine propulsion system to the plenum; and

a valve interconnected with the conduit for regulating pressure of the plenum.

12. The actuation mechanism of claim 11 wherein the pneumatic actuation mechanism further comprises:

a thruster positioned alongside the plenum and connected to a forward end of the retractable port; and

a nozzle extending through the thruster and configured to receive pressurized air from the plenum;

wherein the nozzle is angled to produce thrust to translate the retractable port in the second direction.

13. The actuation mechanism of claim 11 wherein the retractable port comprises:

a head configured as a seal such that the retractable port extends from the compartment of the inner flow duct to close off the bypass passage;

a tail disposed at an aft end of the retractable port and configured for connecting with the mechanical actuation system; and

a leaf spring disposed about the retractable port for retaining the retractable port within the compartment and for sealing pressurized air within the compartment.

14. The actuation mechanism of claim 13 wherein the pneumatic actuation mechanism further comprises a pressure port within the compartment to direct pressurized air from the plenum into the compartment to bias the retractable port in the second direction.

15. The actuation mechanism of claim 8 wherein the pneumatic actuation mechanism includes a pneumatic thruster and a pneumatic piston.

16. An exhaust duct actuation mechanism for use in a convertible gas turbine propulsion system, the actuation mechanism comprising:

a first exhaust duct comprising;

a first end configured for receiving exhaust gas from the convertible gas turbine propulsion system; and

a second end radially larger than the first end;

an inner flow diverter positioned within the second end of the first exhaust duct to define a bypass passage;

a retractable cowling positioned within the inner flow diverter, wherein the cowling is moveable to a first position to close-off the bypass passage, and wherein the cowling is moveable to a second position to open the flow path to ambient pressure; and

a pneumatic actuator connected to the retractable cowling for moving the retractable cowling between the first position and the second position.

17. An actuation mechanism for use in a convertible gas turbine propulsion system, the actuation mechanism comprising:

a plenum for receiving pressurized air from the convertible gas turbine propulsion system;

a pneumatically powered drive body connected to the plenum to receive pressurized air for axially moving the drive body in a first direction, the pneumatically powered drive body comprising;

an elongate thruster positioned alongside the plenum; and

a nozzle extending through the thruster and configured to receive pressurized air from the plenum;

a spring system connected to the drive body for axially moving the drive body in a second direction, the spring system comprising;

a stopper disposed axially aft of the elongate thruster; and

a spring disposed between the aft end of the elongate thruster and the stopper, wherein the nozzle is angled to produce thrust in the first direction to react the spring system; and

a retractable annular port comprising;

a forward end connected with the thruster;

an aft end connected with the spring; and

a central port positioned between the forward end and the aft end and disposed to open and close a pressure chamber within the convertible gas turbine propulsion system.

18. The actuation mechanism of claim 17 and further comprising a bleed air system comprising:

conduit for delivering air compressed in a compressor section of the convertible gas turbine propulsion system to the plenum; and

a valve interconnected with the conduit for regulating pressure of the plenum.