AIRCRAFT ENGINE WITH CLUTCH AND MECHANICAL LOCK

• US 20200130821A1
• Filed: 10/29/2018
• Published: 04/30/2020
• Est. Priority Date: 10/29/2018
• Status: Active Grant

• Current Assignee: Pratt & Whitney Canada Corporation (Rtx Corporation)
• Original Assignee: Pratt & Whitney Canada Corporation (Rtx Corporation)
• Inventors: BERUBE, Stephane, VILLENEUVE, Bruno
• Granted Patent: US 11,267,563 B2
• Time in Patent Office: Days
• CPC Class Codes: B60K 17/26 characterised by arrangement, location, of type of freewheel device
• CPC Class Codes: B60T 1/005 by locking of wheel or transmission rotation
• CPC Class Codes: B60T 1/062 acting on transmission parts
• CPC Class Codes: B64C 27/12 Rotor drives
• CPC Class Codes: B64C 27/14 Direct drive between power plant and rotor hub
• CPC Class Codes: B64D 41/00 Power installations for auxiliary purposes
• CPC Class Codes: F01C 11/008 and of complementary function, e.g. internal combustion engine with supercharger
• CPC Class Codes: F02C 6/206 the vehicles being airscrew driven
• CPC Class Codes: F16D 1/108 having retaining means rotating with the coupling and acting by interengaging parts, i.e. positive coupling
• CPC Class Codes: F16D 11/10 with clutching members movable only axially
• CPC Class Codes: F16D 55/02 with axially-movable discs or pads pressed against axially-located rotating members
• CPC Class Codes: F16D 63/006 Positive locking brakes
• CPC Class Codes: F16D 65/183 with force-transmitting members arranged side by side acting on a spot type force-applying member
• CPC Class Codes: F16H 1/28 with gears having orbital motion

Abstract

There is disclosed an aircraft engine assembly including an engine having an engine shaft; an output shaft; a clutch in driving engagement between the engine shaft and the output shaft. The clutch has a first component in driving engagement with the engine shaft and a second component. The clutch is operable between first and second configurations. In the first configuration, the first component is rotatable relative to the second component and the engine shaft is rotatable relative to the output shaft. In the second configuration, the first and second components are engaged with one another and the engine shaft rotates with the output shaft. A mechanical lock is operable between first and second positions. In the first position, the mechanical lock is disengaged from the first component. In the second position, the first and second components are secured for joint rotation one relative to the other.

Claims

1. An aircraft engine assembly comprising:

an engine having an engine shaft;

an output shaft;

a clutch in driving engagement between the engine shaft and the output shaft, the clutch having a first component in driving engagement with the engine shaft and a second component, the clutch operable between a first configuration and a second configuration, in the first configuration the first component is rotatable relative to the second component and the engine shaft is rotatable relative to the output shaft, in the second configuration the first and second components are engaged with one another such that rotation of the first component relative to the second component is limited and the engine shaft rotates with the output shaft, the clutch configured to selectively engage the engine shaft to the output shaft via the engagement between the first component and the second component;

a mechanical lock operable between a first position and a second position, in the first position the mechanical lock is disengaged from the first component of the clutch, and in the second position the first component and the second component of the clutch are secured for joint rotation one relative to the other.

2. The aircraft engine of claim 1, further comprising a gear train including a driver sun gear secured to the engine shaft, a driven sun gear, planet gears meshed with both of the driver sun gear and the driven sun gear, and a planet carrier rotatably supporting the planet gears, the output shaft drivingly engaged to one of the driven sun gear and the planet carrier, the other of the driven sun gear and the planet carrier rotating upon rotation of the engine shaft in the first configuration of the clutch, rotation of the other of the driven sun gear and the planet carrier limited by the clutch in the second configuration of the clutch.

3. The aircraft engine of claim 2, wherein the first component of the clutch is a disk secured to the other of the driven sun gear and the planet carrier, the second component of the clutch being a braking member operable between a free configuration in which the disk and the braking member are rotatable relative to one another and a braking configuration in which the braking member limits rotation of the disk relative to the braking member.

4. The aircraft engine of claim 3, wherein the braking member includes braking pads receiving the disk therebetween, the brake pads in contact with the disk in the braking configuration for limiting rotation of the disk by friction.

5. The aircraft engine of claim 1, wherein the mechanical lock includes a rod and an actuator engaged to the rod, the actuator operable to move the rod between the first and second positions of the mechanical lock.

6. The aircraft engine of claim 5, wherein the actuator is a solenoid.

7. The aircraft engine of claim 5, wherein a de-energized position of the mechanical lock corresponds to the second position.

8. The aircraft engine of claim 1, wherein the clutch is a torque converter, the first component being an input of the torque converter in driving engagement with the engine shaft and the second component being engaged to an output of the torque converter, the output in driving engagement with the output shaft, the input drivingly engageable to the output via a fluid contained in the torque converter, the mechanical lock engaging the engine shaft with the output of the torque converter in the second position of the mechanical lock.

9. The aircraft engine of claim 8, wherein the mechanical lock is a dog clutch having a first part in driving engagement with the input of the torque converter and a second part in driving engagement with the output shaft, one of the first part and the second part having male members and the other of the first part and the second part having female members engaged by the male members in the second position of the mechanical lock.

10. An aircraft engine comprising:

an intermittent internal combustion engine having an engine shaft;

a turbine having a turbine shaft drivingly engaged to the engine shaft, the turbine having a turbine inlet fluidly connected to an exhaust of the intermittent internal combustion engine;

an output shaft operatively connectable to a rotatable load;

a clutch in driving engagement between the engine shaft and the output shaft, the clutch having a first component in driving engagement with the engine shaft and a second component, the clutch operable between a first configuration and a second configuration, in the first configuration the first component is rotatable relative to the second component and the engine shaft is rotatable relative to the output shaft, in the second configuration the first and second components are engaged with one another such that rotation of the first component relative to the second component is limited and the engine shaft rotates with the output shaft, the clutch configured to selectively engage the engine shaft to the output shaft via the engagement between the first component and the second component;

a mechanical lock operable between a first position and a second position, in the first position the mechanical lock is disengaged from the first component of the clutch, and in the second position the first component and the second component of the clutch are secured for joint rotation one relative to the other.

11. The aircraft engine of claim 10, wherein the intermittent internal combustion engine is a rotary engine.

12. The aircraft engine of claim 10, further comprising a compressor in driving engagement with the turbine shaft, the compressor having a compressor outlet fluidly connected to an inlet of the intermittent internal combustion engine.

13. The aircraft engine of claim 10, further comprising a gear train including a driver sun gear secured to the engine shaft, a driven sun gear, planet gears meshed with both of the driver sun gear and the driven sun gear, and a planet carrier rotatably supporting the planet gears, the output shaft drivingly engaged to one of the driven sun gear and the planet carrier, the other of the driven sun gear and the planet carrier rotating upon rotation of the engine shaft in the first configuration of the clutch, rotation of the other of the driven sun gear and the planet carrier limited by the clutch in the second configuration of the clutch.

14. The aircraft engine of claim 13, wherein the first component of the clutch is a disk secured to the other of the driven sun gear and the planet carrier, the second component of the clutch being a braking member operable between a free configuration in which the disk and the braking member are rotatable relative to one another and a braking configuration in which the braking member limits rotation of the disk relative to the braking member.

15. A method of operating an aircraft engine comprising:

rotating an engine shaft of an engine;

starting rotation of a rotatable load by progressively increasing a magnitude of a torque transmitted from the engine shaft to an output shaft in driving engagement with the rotatable load;

when the rotatable load reaches a given rotational speed, locking the output shaft to the engine shaft; and

increasing a rotational speed of the rotatable load beyond the given rotational speed.

16. The method of claim 15, wherein starting rotation of the rotatable load includes:

rotating a driver sun gear in driving engagement with the engine shaft thereby rotating one of a driven sun gear and a planet carrier rotatably supporting planet gears meshed with the driving sun gear and the driven sun gear, the output shaft in driving engagement with the other of the driven sun gear and the planet carrier; and

decelerating rotation of the one of the driven sun gear and the planet carrier thereby accelerating rotation of the other of the driven sun gear and the planet carrier.

17. The method of claim 16, wherein decelerating the one of the driven sun gear and the planet carrier includes exerting a force on the one of the driven sun gear and the planet carrier.

18. The method of claim 17, wherein exerting a force on the one of the driven sun gear and the planet carrier includes exerting a friction force on a surface of the one of the driven sun gear and the planet carrier.

19. The method of claim 15, wherein locking the output shaft to the engine shaft includes operating a mechanical lock from a first position in which the engine shaft is rotatable relative to the output shaft to a second position in which the engine shaft is rotatably locked to the output shaft, the engine shaft and the output shaft in joint rotation with each other in the second position of the mechanical lock.

20. The method of claim 19, wherein operating the mechanical lock includes moving a rod with an actuator engaged to the rod.