Electrical machines for integration into a propulsion engine

1. An electrical machine comprising:

a stator assembly coupled to an engine stator component of a propulsion engine, the stator assembly comprising:

a stator support assembly fixedly attached to the engine stator component; and

a stator disposed on a supporting surface of the stator support structure; and

an electrical machine shaft coupled to an end of a shaft of the propulsion engine via an intermediate shaft member extending axially between the end of the shaft and the electrical machine shaft;

a bearing support frame extending from the propulsion engine, the bearing support frame defining a bearing cavity in conjunction with the electrical machine shaft;

first and second electrical machine bearings radially extending from the bearing support frame to rotatably contact the electrical machine shaft;

a sealing member disposed axially aft of the electrical machine bearings, the sealing member extending from the bearing support frame to the electrical machine shaft;

a rotor support structure connected to the electrical machine shaft; and

a rotor attached to the rotor support structure, wherein the rotor rotates in conjunction with the electrical machine shaft to exchange energy with the shaft of the propulsion engine.

2. The electrical machine of claim 1 , wherein:

the bearing cavity is defined by the bearing support frame in conjunction with the electrical machine shaft, and

an engine bearing of the propulsion engine is disposed within the bearing cavity.

3. The electrical machine of claim 2 , further comprising:

an oil supply line extending through the bearing support frame into a common sump defined at least in part between the bearing support frame and the electrical machine shaft;

a first oil nozzle extending from the oil supply line and disposed proximate to the electrical machine bearings; and

a second oil nozzle extending from the oil supply line and disposed proximate to the engine bearing.

4. The electrical machine of claim 3 , wherein:

the stator assembly comprises a stator support arm connected to the engine stator component via an axial portion of the bearing support frame; and

the oil supply line extends through the axial portion of the bearing support frame into the common sump.

5. The electrical machine of claim 1 , further comprising an engine bearing support arm connected to the second engine stator component, the engine bearing support arm defining an engine bearing cavity in conjunction with the shaft of the propulsion engine.

6. The electrical machine of claim 5 , further comprising a first sealing member and a second sealing member extending between the bearing support frame and the electrical machine shaft to seal off the bearing cavity.

7. The electrical machine of claim 6 , further comprising:

a first oil supply line extending through the bearing support frame into the bearing cavity; and

a second oil supply line extending into the engine bearing cavity.

8. The electrical machine of claim 1 , further comprising a decoupling device attached to the propulsion engine, the decoupling device axially overlapping the intermediate shaft member such that the decoupling device decouples the intermediate shaft member upon activation.

9. The electrical machine of claim 1 , wherein the intermediate shaft member permits movement of the electrical machine shaft relative to the shaft of the propulsion engine in an axial direction and a radial direction.

10. The electrical machine of claim 9 , wherein the intermediate shaft comprises a quill shaft comprising a first spline disposed at a first end thereof and a second spline disposed at a second end thereof, wherein the first and second splines are inserted into openings at ends of the shaft of the propulsion engine and the electrical machine shaft to permit the movement of the electrical machine shaft in the axial and radial directions.

11. The electrical machine of claim 1 , wherein entireties of the rotor and the rotor support structure are disposed radially inward of the stator assembly.

12. The electrical machine of claim 1 , wherein the rotor support structure is connected to an end of the electrical machine shaft by a removable connection such that the rotor support structure and rotor are independently removable from the propulsion engine.

13. The electrical machine of claim 1 , wherein the intermediate shaft comprises a shear section structured to decouple when placed under a predetermined shear load.

14. A propulsion engine comprising:

a core portion generating exhaust that travels in an axial direction;

a turbine section coupled to a shaft, wherein the turbine section receives the exhaust and generates mechanical energy to rotate the shaft;

a turbine frame attached to the turbine section, the turbine frame comprising:

an outer casing coupled to the turbine section; and

an inner hub supporting the shaft via a bearing assembly comprising an engine bearing supporting the shaft; and

an electrical machine comprising:

a stator assembly comprising a stator support assembly attached to the inner hub and a stator attached to the stator support structure;

an electrical machine shaft coupled to an end of the shaft via an intermediate shaft member extending axially between the end of the shaft and the electrical machine shaft;

a bearing support frame attached to the inner hub and extending radially inward therefrom to define a bearing cavity extending between the bearing support frame and electrical machine shaft;

electrical machine bearings radially extending from the bearing support frame to rotatably contact the electrical machine shaft; and

a rotor assembly comprising:

a rotor support structure connected to the electrical machine shaft; and

a rotor attached to the rotor support structure and extending radially inward of the stator, wherein the rotor rotates in conjunction with the shaft via the intermediate shaft member to exchange energy with the shaft.

15. The propulsion engine of claim 14 , wherein:

the turbine frame further comprises a plurality of struts extending between the outer casing and the inner hub, and

at least one of the plurality of struts defines an internal cavity having a cooling duct disposed therein.

16. The propulsion engine of claim 15 , wherein the electrical machine further comprises a cooling system comprising a stator manifold to provide coolant from a coolant source to the stator assembly and the rotor assembly.

17. The propulsion engine of claim 14 , wherein the intermediate shaft member and the electrical machine shaft are an integrated component.

18. The propulsion engine of claim 14 , further comprising a decoupling device axially overlapping the intermediate shaft member such that the decoupling device decouples the intermediate shaft member upon activation.

19. The propulsion engine of claim 14 , wherein the intermediate shaft member permits movement of the electrical machine shaft relative to the shaft of the propulsion engine in an axial direction and a radial direction.

20. The propulsion engine of claim 14 , further comprising a sealing member extending between the bearing support frame and the electrical machine shaft to seal the bearing cavity.