Granted Patent B2

US 12,480,450 · App. 17/359,891 · Granted Nov 25, 2025

Inventors: Michael D. Greenberg (Bloomfield, CT); Lance L. Smith (West Hartford, CT); Dennis P. Cronin (Lebanon, CT); Nancy Poisson (Avon, CT); Christopher D. Ramsey (Glastonbury, CT); Neil Terwilliger (Meriden, CT)

Assignee: RTX CORPORATION

F02C7/36F05D2220/76

Abstract

Claims (41)

1 . A hybrid electric engine of an aircraft, comprising:

a high pressure compressor located at and rotatable about an engine central longitudinal axis;

a high pressure turbine located at and rotatable about the engine central longitudinal axis, the high pressure turbine operably connected to the high pressure compressor via a variable gear ratio gearbox;

a combustor configured to drive the high pressure turbine via a flow of combustion products; and

an electric motor operably connected to the variable gear ratio gearbox and configured to input rotational energy into the variable gear ratio gearbox;

wherein the rotational energy inputted into the variable gear ratio gearbox from the electric motor changes a rotational speed of one of the high pressure compressor or the high pressure turbine relative to the other of the high pressure compressor or the high pressure turbine;

wherein the variable gear ratio gearbox is located axially between the high pressure compressor and the high pressure turbine;

wherein:

the variable gear ratio gearbox is operably connected to the high pressure turbine via a first tower shaft operably connected to a turbine shaft at a first axial end of the high pressure compressor; and

the variable gear ratio gearbox is operably connected to the high pressure compressor via a second tower shaft operably connected to a compressor shaft at a second axial end of the high pressure compressor opposite the first axial end;

wherein the compressor shaft is located radially outboard of the turbine shaft and axially overlaps the turbine shaft.

2 . The hybrid electric engine of claim 1 , wherein the rotational energy accelerates the high pressure compressor relative to the high pressure turbine.

3 . The hybrid electric engine of claim 1 , wherein the rotational energy decelerates the high pressure compressor relative to the high pressure turbine.

4 . The hybrid electric engine of claim 1 , wherein in the variable gear ratio gearbox includes a planetary gear arrangement.

5 . The hybrid electric engine of claim 1 , wherein the electric motor is a variable speed electric motor.

6 . The hybrid electric engine of claim 1 , further comprising:

a compressor speed sensor configured to detect a compressor shaft speed; and

a turbine speed sensor configured to detect a turbine shaft speed;

wherein operation of the electric motor is selectably changed as a result of the detected compressor shaft speed and the detected turbine shaft speed.

7 . The hybrid electric engine of claim 1 , wherein the electric motor includes a brake mechanism to stop rotation of the electric motor.

8 . A method of operating a hybrid electric engine, comprising:

combusting a fuel at a combustor;

driving a high pressure turbine about an engine central longitudinal axis via products of combusting the fuel at the combustor;

driving a high pressure compressor about the engine central longitudinal axis via driving of the high pressure turbine, the high pressure turbine and the high pressure compressor operably connected to a variable gear ratio gearbox;

inputting rotational energy from an electric motor into the variable gear ratio gearbox;

changing a rotational speed of the high pressure compressor relative to the high pressure turbine via inputting the rotational energy into the variable gear ratio gearbox;

wherein the variable gear ratio gearbox is located remotely from the engine central longitudinal axis;

wherein the variable gear ratio gearbox is located axially between the high pressure compressor and the high pressure turbine;

wherein:

the variable gear ratio gearbox is operably connected to the high pressure turbine via a first tower shaft operably connected to a turbine shaft at a first axial end of the high pressure compressor; and

the variable gear ratio gearbox is operably connected to the high pressure compressor via a second tower shaft operably connected to a compressor shaft at a second axial end of the high pressure compressor opposite the first axial end;

wherein the compressor shaft is located radially outboard of the turbine shaft and axially overlaps the turbine shaft.

9 . The method of claim 8 , further comprising accelerating the high pressure compressor relative to the high pressure turbine by inputting the rotational energy.

10 . The method of claim 9 , wherein the rotational speed of the high pressure compressor is increased by up to about 30% relative to a rotational speed of the high pressure turbine.

11 . The method of claim 8 , further comprising decelerating the high pressure compressor relative to the high pressure turbine by inputting the rotational energy.

12 . The method of claim 8 , wherein a default speed ratio of the high pressure compressor to the high pressure turbine without inputting the rotational energy from the electric motor is other than 1:1.

13 . The method of claim 8 , further comprising varying a speed of the electric motor.

14 . The method of claim 8 , further comprising:

detecting a compressor shaft speed via a compressor speed sensor;

detecting a turbine shaft speed via a turbine speed sensor; and

selectably changing operation of the electric motor as a result of the detected compressor shaft speed and the detected turbine shaft speed.

Assignments (3)

Continuity (1)

References Cited (17)