POWER PLANT MANAGEMENT SYSTEM FOR DUAL ENGINE HELICOPTER IN SINGLE ENGINE OPERATION MODE

• US 20170327241A1
• Filed: 01/23/2017
• Published: 11/16/2017
• Est. Priority Date: 04/27/2016
• Status: Active Grant

• Current Assignee: Pratt & Whitney Canada Corporation (Rtx Corporation)
• Original Assignee: Pratt & Whitney Canada Corporation (Rtx Corporation)
• Inventors: MITROVIC, Lazar, DUROCHER, Eric, MORGAN, Keith
• Granted Patent: US 10,577,118 B2
• Time in Patent Office: Days
• CPC Class Codes: B64C 27/12 Rotor drives
• CPC Class Codes: B64D 27/10 of gas-turbine type jet aircraft B64D27/16
• CPC Class Codes: B64D 31/06 actuated automatically
• CPC Class Codes: B64D 35/08 characterised by the transmission being driven by a plurality of power plants
• CPC Class Codes: F02C 6/02 Plural gas-turbine plants having a common power output
• CPC Class Codes: F02C 7/22 Fuel supply systems
• CPC Class Codes: F02C 7/26 Starting; Ignition
• CPC Class Codes: F02C 7/262 Restarting after flame-out
• CPC Class Codes: F02C 7/275 Mechanical drives
• CPC Class Codes: F02C 7/32 Arrangement, mounting, or driving, of auxiliaries
• 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 2220/323 for aircraft propulsion, e.g. jet engines
• CPC Class Codes: F05D 2220/329 in helicopters
• CPC Class Codes: F05D 2260/4023 through a friction clutch
• CPC Class Codes: F05D 2260/404 through magnetic drive coupling
• CPC Class Codes: F05D 2260/85 Starting
• CPC Class Codes: F05D 2260/902 using frictional mechanical forces
• CPC Class Codes: F05D 2260/903 using electrical or magnetic forces
• CPC Class Codes: F16D 48/02 Control by fluid pressure
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A method of operating a twin engine helicopter power plant, the power plant comprising: two turboshaft engines each having an engine shaft with a turbine at a distal end and a one-way clutch at a proximal end; a gear box having an input driven by the one way clutch of each engine and an output driving a helicopter rotor; a bypass clutch disposed between the proximal end of each engine shaft and the input of the gear box; and power plant management system controls for activating the bypass clutch; the method comprising: detecting when a rotary speed of an associated engine shaft is less than a rotary speed of the gear box input; activating the bypass clutch to drive the associated engine shaft using the rotation of the gear box input; and starting an associated engine by injecting fuel when the bypass clutch is activated.

Claims

1. A helicopter power plant comprising:

at least two turboshaft engines each having an engine shaft with a turbine at a distal end and a one-way clutch at a proximal end;

a gear box having an input driven by the one way clutch of each engine and an output driving a helicopter rotor;

a bypass clutch disposed between the proximal end of at least one of the engine shafts and the input of the gear box; and

power plant controls for activating the bypass clutch when a rotary speed of an associated engine shaft is less than a rotary speed of the gear box input.

2. The helicopter power plant according to claim 1 wherein the bypass clutch is co-axial with the one-way clutch.

3. The helicopter power plant according to claim 2 wherein the bypass clutch has one of:

annular friction plates; and

conical friction surfaces.

4. The helicopter power plant according to claim 2 wherein the bypass clutch is one of:

a hydraulic clutch; and

a magnetic clutch.

5. The helicopter power plant according to claim 1 wherein the bypass clutch is axially spaced from the one-way clutch.

6. The helicopter power plant according to claim 5 wherein the bypass clutch is one of:

a friction clutch;

a hydraulic clutch;

and a magnetic clutch.

7. A helicopter comprising:

two turboshaft engines each having an engine shaft with a turbine at a distal end and a one-way clutch at a proximal end;

a gear box having an input driven by the one way clutch of each engine and an output driving a helicopter rotor;

a bypass clutch disposed between the proximal end of each engine shaft and the input of the gear box; and

power plant controls for activating the bypass clutch when a rotary speed of an associated engine shaft is less than a rotary speed of the gear box input.

8. The helicopter according to claim 7 wherein the bypass clutch is co-axial with the one-way clutch.

9. The helicopter according to claim 8 wherein the bypass clutch has one of:

annular friction plates; and

conical friction surfaces.

10. The helicopter according to claim 8 wherein the bypass clutch is one of:

a hydraulic clutch; and

a magnetic clutch.

11. The helicopter according to claim 7 wherein the bypass clutch is axially spaced from the one-way clutch.

12. The helicopter according to claim 11 wherein the bypass clutch is one of:

a friction clutch;

a hydraulic clutch; and

a magnetic clutch.

19. The method according to claim 7 wherein the bypass clutch is axially spaced from the one-way clutch.

20. The helicopter power plant according to claim 19 wherein the bypass clutch is one of:

a friction clutch;

a hydraulic clutch; and

a magnetic clutch.

13. A method of operating a twin engine helicopter power plant, the power plant comprising:

two turboshaft engines each having an engine shaft with a turbine at a distal end and a one-way clutch at a proximal end;

a gear box having an input driven by the one way clutch of each engine and an output driving a helicopter rotor;

a bypass clutch disposed between the proximal end of each engine shaft and the input of the gear box; and

power plant management system controls for activating the bypass clutch;

the method comprising;

detecting when a rotary speed of an associated engine shaft is less than a rotary speed of the gear box input;

activating the bypass clutch to drive the associated engine shaft using the rotation of the gear box input; and

starting an associated engine by injecting fuel when the bypass clutch is activated.

14. The method according to claim 13 wherein the associated engine includes a starter motor, the method comprising:

activating the starter motor and the bypass clutch simultaneously.

15. The method according to claim 13 wherein the twin engine helicopter power plant is operated in single engine operation wherein an associated engine is shut down during flight.

16. The method according to claim 13 wherein the associated engine and bypass clutch are driven by autorotation of the helicopter rotor.

17. The method according to claim 16 wherein the bypass clutch has one of:

annular friction plates; and

conical friction surfaces.

18. The method according to claim 16 wherein the bypass clutch is one of:

a hydraulic clutch; and

a magnetic clutch.