Hybrid aircraft propulsion power plants

Patent metadata

Field	Value
Publication number	US-11485503-B2
Application number	US-202016830422-A
Country	US
Kind code	B2
Filing date	Mar 26, 2020
Priority date	Mar 29, 2019
Publication date	Nov 1, 2022
Grant date	Nov 1, 2022

Abstract

An aircraft power plant has a hybrid propulsion system having an electric motor, a combustion engine, an output shaft drivingly connectable to a thrust generator, a compressor, and a transmission having a first transmission drive path and a second transmission drive path, the combustion engine and the output shaft in driving engagement with the first transmission drive path, the electric motor selectively drivingly engageable to the compressor via either the first drive path or via the second drive path.

First claim

The invention claimed is:

1. An aircraft power plant comprising:
a transmission having a first transmission drive path and a second transmission drive path;
a combustion engine in driving engagement with the first transmission drive path;
an output shaft drivingly connectable to a thrust generator, the output shaft in driving engagement with the first transmission drive path;
a compressor; and
an electric motor,
the electric motor selectively drivingly engageable to the compressor via either the first transmission drive path or via the second transmission drive path.

2. The aircraft power plant of claim 1 , wherein the transmission includes an engagement device operable in an Auxiliary Power Unit (APU) mode in which a rotational input of the electric motor is transmitted from the electric motor to the compressor via the second drive path and in a propulsion mode in which the rotational input of the electric motor is transmitted from the electric motor to the compressor via the first transmission drive path.

3. The aircraft power plant of claim 2 , wherein the engagement device includes four one-way clutches operatively connected to the second transmission drive path.

4. The aircraft power plant of claim 3 , wherein rotation of the electric motor in a first rotational direction drivingly engages the electric motor to the compressor via the first transmission drive path, rotation of the electric motor in a second rotational direction opposite the first rotational direction drivingly engages the electric motor to the compressor via the second transmission drive path.

5. The aircraft power plant of claim 1 , wherein the transmission includes a planetary gear train having a sun gear, planet gears meshed with the sun gear and rotatably supported by a planet carrier, and a ring gear meshed with the planet gears, the electric motor in driving engagement with a first one of the sun gear, the planet carrier, and the ring gear, the first transmission drive path extending from a second one of the sun gear, the planet carrier, and the ring gear, the second transmission drive path extending from a third one of the sun gear, the planet carrier, and the ring gear, a brake operatively connected to the third one of the sun gear, the planet carrier, and the ring gear and operable in an engaged configuration in which the electric motor engages the compressor via the first transmission drive path and in a disengaged configuration in which the electric motor engages the compressor via the second transmission drive path.

6. The aircraft power plant of claim 5 , wherein the electric motor is in driving engagement with the sun gear, the first transmission drive path extending from the planet carrier, the second transmission drive path extending from the ring gear, the brake operatively connected to the ring gear to selectively limit or allow rotation of the ring gear.

7. The aircraft power plant of claim 6 , wherein the output shaft is in driving engagement with the planet carrier.

8. The aircraft power plant of claim 5 , wherein one-way clutches are operatively connected to the second transmission drive path.

9. The aircraft power plant of claim 8 , wherein, in the engaged configuration of the brake, a rotational input from the electric motor is transmitted to the compressor and a rotation of the compressor is isolated from the second transmission drive path via one of the one-way clutches.

10. An aircraft power plant comprising:
a transmission having a first transmission drive path and a second transmission drive path;
a combustion engine drivingly engagement with the first transmission drive path and excluded from the second transmission drive path;
an output shaft drivingly connectable to a thrust generator, the output shaft drivingly engaged to the first transmission drive path and excluded from the second transmission drive path;
a compressor; and
an electric motor selectively drivingly engageable to the compressor via either of the first and second transmission drive paths, both of the first transmission drive path and the second transmission drive path extending from the electric motor to the combustion engine.

11. The aircraft power plant of claim 10 , wherein the transmission includes an engagement device operable in an Auxiliary Power Unit (APU) mode in which a rotational input of the electric motor is transmitted to the compressor via the second drive path and bypasses the combustion engine and in a propulsion mode in which the rotational input of the electric motor is transmitted to the compressor via the first transmission drive path.

12. The aircraft power plant of claim 11 , wherein the engagement device includes four one-way clutches operatively connected to the second transmission drive path.

13. The aircraft power plant of claim 12 , wherein rotation of the electric motor in a first rotational direction drivingly engages the electric motor to the compressor via the first transmission drive path, rotation of the electric motor in a second rotational direction opposite the first rotational direction drivingly engages the electric motor to the compressor via the second transmission drive path.

14. The aircraft power plant of claim 10 , wherein the transmission includes a planetary gear train having a sun gear, planet gears meshed with the sun gear and rotatably supported by a planet carrier, and a ring gear meshed with the planet gears, the electric motor in driving engagement with a first one of the sun gear, the planet carrier, and the ring gear, the first transmission drive path extending from a second one of the sun gear, the planet carrier, and the ring gear, the second transmission drive path extending from a third one of the sun gear, the planet carrier, and the ring gear, a brake operatively connected to the third one of the sun gear, the planet carrier, and the ring gear and operable in an engaged configuration in which the electric motor engages the compressor via the first transmission drive path and in a disengaged configuration in which the electric motor engages the compressor via the second transmission drive path.

15. The aircraft power plant of claim 14 , wherein the electric motor is in driving engagement with the sun gear, the first transmission drive path extending from the planet carrier, the second transmission drive path extending from the ring gear, the brake operatively connected to the ring gear to selectively limit or allow rotation of the ring gear.

16. The aircraft power plant of claim 14 , wherein two one-way clutches are operatively connected to the second transmission drive path.

17. The aircraft power plant of claim 16 , wherein, in the engaged configuration of the brake, a rotational input from the electric motor is transmitted to the compressor and a rotation of the compressor is isolated from the second transmission drive path via one of the two one-way clutches.

18. The aircraft power plant of claim 17 , wherein the output shaft is in driving engagement with the planet carrier.

19. A method of operating an aircraft power plant having a hybrid propulsion system including an electric motor, an output shaft drivingly connectable to a thrust generator, a combustion engine, a compressor, comprising:
in an Auxiliary Power Unit (APU) mode, transmitting a first rotational input from the electric motor to the compressor along a first drive path while maintaining a second rotational input from the combustion engine separate from the output shaft; and
in a propelling mode, compounding the first rotational input and the se

Assignees

• Pratt & Whitney Canada

Inventors

• Dubreuil Jean
• Ullyott Richard

Classifications

• Y02T50/60

  Efficient propulsion technologies, e.g. for aircraft · CPC title

• B64D41/00

  Power installations for auxiliary purposes · CPC title

• F02C7/32

  Arrangement, mounting, or driving, of auxiliaries · CPC title

• B60W20/40

  Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers {(power-up or power-down of the driveline B60W30/192)} · CPC title

• F02C7/36

  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 title