Differential driven open rotor with brake

Patent metadata

Field	Value
Publication number	US-12565328-B2
Application number	US-202418773027-A
Country	US
Kind code	B2
Filing date	Jul 15, 2024
Priority date	Jul 15, 2024
Publication date	Mar 3, 2026
Grant date	Mar 3, 2026

Abstract

An assembly for an aircraft propulsion system includes an open propulsor rotor and a powertrain configured to receive power from a turbine and drive both the propulsor rotor and a compressor section at the same time in a first mode of operation. In a second mode of operation, a brake is applied that stops rotation of the propulsor rotor and the turbine power received by the powertrain drives only the compressor section. In the second mode, the propulsor rotor is stationary or otherwise undriven which effectively prevents rotation of the propulsor rotor. This reduces or eliminates safety risks to ground crews resulting from an open propulsor rotor actively rotating as the aircraft is on the ground.

First claim

What is claimed is:

1 . An assembly for an aircraft propulsion system, comprising:
a gas turbine engine core including a low pressure (LP) compressor section, a high pressure (HP) compressor section, a combustion section, a HP turbine section, a LP turbine section, a HP drive shaft coupled to the HP turbine section and the HP compressor section, and an LP turbine drive shaft coupled to the LP turbine section; a propulsor rotor coupled to a propulsor rotor drive shaft; an LP compressor drive shaft coupled to the LP compressor section; a powertrain comprising,
a first input coupled to the LP turbine drive shaft,
a first output coupled to the LP compressor drive shaft, and
a second output coupled to the propulsor rotor drive shaft; and
the powertrain configured to:
transfer power from the LP turbine drive shaft to the propulsor rotor drive shaft and the LP compressor drive shaft during a first mode of operation when a propulsor rotor brake is disengaged, and
transfer power from the LP turbine drive shaft to the LP compressor drive shaft during a second mode of operation when the propulsor rotor brake is engaged.

2 . The assembly in accordance with claim 1 , wherein the powertrain further comprises:
an epicyclic gearset.

3 . The assembly in accordance with claim 1 , wherein the powertrain further comprises:
a sun gear rotatable about a centerline axis; a ring gear circumscribing the sun gear and rotatable about the centerline axis; a plurality of intermediate gears arranged circumferentially about the centerline axis, each of the plurality of intermediate gears meshed between the sun gear and the ring gear; and a carrier rotatable about the centerline axis, each of the plurality of intermediate gears rotatably mounted to the carrier.

4 . The assembly in accordance with claim 3 wherein, when in the first mode of operation, the sun gear rotates about the centerline axis in a first direction, the ring gear rotates about the centerline axis in a second direction opposite the first direction, and the carrier rotates about the centerline axis in the first direction.

5 . The assembly in accordance with claim 3 wherein, when in the second mode of operation, the sun gear rotates about the centerline axis in a first direction, the ring gear rotates about the centerline axis in a second direction opposite the first direction, and the carrier does not rotate about the centerline axis.

6 . The assembly in accordance with claim 1 , further comprising:
a load coupled to the LP compressor drive shaft.

7 . The assembly in accordance with claim 1 , further comprising:
a load coupled to the LP turbine drive shaft.

8 . The assembly in accordance with claim 1 , further comprising:
the propulsor rotor brake is configured to place the assembly in the first mode of operation when not engaged and place the assembly in the second mode of operation when engaged.

9 . The assembly in accordance with claim 8 , wherein when the propulsor rotor brake is engaged, the propulsor rotor brake is configured to stop and prevent rotation of the propulsor rotor drive shaft.

10 . An aircraft propulsion system, comprising:
a core engine defining an engine airflow path, the core engine comprising:
a first spool section having a first compressor, a combustion section, a first turbine and a first spool shaft coupled to the first compressor and the first turbine,
a second turbine coupled to an input drive shaft, and
a second compressor coupled to a first output drive shaft;
an open propulsor rotor disposed near one end of the core engine and coupled to a second output drive shaft, the open propulsor rotor comprising a plurality of rotor blades; and a powertrain assembly coupled to the input drive shaft and the first and second output drives shafts, the powertrain assembly configured to:
transfer power from the input drive shaft to the first output drive shaft and the second output drive shaft during a first mode, and
transfer power from the input drive shaft only to the first output drive shaft during a second mode when the second output drive shaft is prevented from rotating.

11 . The aircraft propulsion system in accordance with claim 10 , wherein the powertrain assembly further comprises:
an epicyclic gearset.

12 . The aircraft propulsion system in accordance with claim 11 , wherein the epicyclic gearset comprises:
a sun gear rotatable about a centerline axis; a ring gear circumscribing the sun gear and rotatable about the centerline axis; a plurality of intermediate gears arranged circumferentially about the centerline axis, each of the plurality of intermediate gears meshed between the sun gear and the ring gear; and a carrier rotatable about the centerline axis, each of the plurality of intermediate gears rotatably mounted to the carrier.

13 . The aircraft propulsion system in accordance with claim 12 , wherein when in the first mode, the sun gear rotates about the centerline axis in a first direction, the ring gear rotates about the centerline axis in a second direction opposite the first direction, and the carrier rotates about the centerline axis in the first direction.

14 . The aircraft propulsion system in accordance with claim 12 , wherein when in the second mode, the sun gear rotates about the centerline axis in a first direction, the ring gear rotates about the centerline axis in a second direction opposite the first direction, and the carrier does not rotate about the centerline axis.

15 . The aircraft propulsion system in accordance with claim 10 , further comprising:
a brake configured to inhibit and stop rotation of the second output drive shaft and prevent the second output drive shaft from rotating.

16 . The aircraft propulsion system in accordance with claim 10 , further comprising:
a brake configured to cause the aircraft propulsion system to operate in the first mode when disengaged and cause the aircraft propulsion system to operate in the second mode when engaged.

17 . The aircraft propulsion system in accordance with claim 10 further comprising:
a load coupled to the first output drive shaft.

18 . An open rotor engine having a single open propulsor rotor, the open rotor engine comprising:
a first compressor, a combustion section, a first turbine and a first drive shaft coupled to the first compressor and the first turbine; a second turbine; a second compressor; and a powertrain operable to:
transfer power received from the second turbine to the single open propulsor rotor and the second compressor during a first mode of operation, and
transfer power received from the second turbine to only the second compressor during a second mode of operation.

19 . The open rotor engine in accordance with claim 18 , further comprising:
a brake configured to place the open rotor engine in the first mode of operation when not engaged and place the open rotor engine in the second mode of operation when engaged.

20 . The open rotor engine in accordance with claim 19 , wherein the powertrain comprises:
an epicyclic gearset.

Assignees

• Rtx Corp

Inventors

• Morton Jeffrey T
• Hanrahan Paul R
• Breault Andrew E
• Sobanski Jon E

Classifications

• F02C3/107

  with two or more rotors connected by power transmission · CPC title

• F05D2260/90

  Braking · CPC title

• F05D2260/40311

  of the epicyclical, planetary or differential type · CPC title

• F05D2220/323

  for aircraft propulsion, e.g. jet engines · CPC title

• F02C7/36 Primary

  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