Air pressurisation system

Patent metadata

Field	Value
Publication number	US-12565320-B2
Application number	US-202418795552-A
Country	US
Kind code	B2
Filing date	Aug 6, 2024
Priority date	Aug 21, 2023
Publication date	Mar 3, 2026
Grant date	Mar 3, 2026

Abstract

There is provided an air pressurisation system for an aircraft, the air pressurisation system comprising: a transmission for driving a rotor of a blower compressor for the air pressurisation system, wherein the transmission comprises: a first input configured to receive drive from a spool of a gas turbine engine; a second input; and an output configured to drive to the rotor of the blower compressor, wherein a speed of the output is determined by a function of speeds of the first and second inputs; and a brake coupled to the second input, wherein the brake is operable to engage and brake the transmission at the second input, in order to fix a transmission ratio of the transmission between the first input and the output.

First claim

The invention claimed is:

1 . An air pressurisation system for an aircraft, the air pressurisation system comprising:
a transmission for driving a rotor of a blower compressor for the air pressurisation system, wherein the transmission comprises:
a first input configured to receive drive from a spool of a gas turbine engine;
a second input; and
an output configured to drive the rotor of the blower compressor, wherein a speed of the output is determined by a function of speeds of the first and second inputs;
and
a brake coupled to the second input, wherein the brake is operable to engage and brake the transmission at the second input, in order to fix a transmission ratio of the transmission between the first input and the output.

2 . The air pressurisation system of claim 1 , wherein the brake is selectively operable to brake the transmission at the second input.

3 . The air pressurisation system of claim 1 , wherein the brake is configured to engage and brake the transmission at the second input when a speed of the transmission at the second input exceeds a predetermined threshold speed.

4 . The air pressurisation system of claim 3 , wherein the brake is configured to disengage, so that the second input is not braked by the brake when a speed of the transmission at the second input reduces below a further predetermined threshold speed.

5 . The air pressurisation system of claim 1 , wherein the transmission comprises a differential epicyclic transmission, wherein the first input is operatively coupled to one of a ring gear and a carrier of the differential epicyclic transmission, the second input is operatively coupled to the other of the ring gear and the carrier, and the output is operatively coupled to a sun gear of the differential epicyclic transmission.

6 . The air pressurisation system of claim 5 , wherein the other of the ring gear and the carrier comprises a gear that meshes with a stepped gear and wherein the brake is meshingly engaged with a step of the stepped gear having a fewer number of teeth than the other step.

7 . The air pressurisation system of claim 1 , wherein the system further comprises an electrical machine, wherein a shaft of the electrical machine is operatively coupled to the second input.

8 . The air pressurisation system of claim 7 , wherein the system further comprises an electrical power management system configured to control a speed of the shaft of the electrical machine.

9 . The air pressurisation system of claim 8 , wherein the system further comprises a further electrical machine, wherein a shaft of the further electrical machine is drivingly coupled with the spool of the gas turbine engine and wherein the further electrical machine is electrically coupled to the electrical power management system.

10 . The air pressurisation system of claim 9 , wherein the system further comprises a controller configured to identify a fault in the further electrical machine, wherein the controller is configured to operate the brake to engage and brake the transmission at the second input, when a fault is identified in the further electrical machine.

11 . The air pressurisation system of claim 1 , wherein the system is configured to operate in a starter mode, in which the transmission is configured to receive drive from the rotor of the blower compressor at the output and supply drive to the spool of the gas turbine engine via the first input, wherein when operating in the starter mode, the brake is configured to engage in order to fix a transmission ratio of the transmission.

12 . The air pressurisation system of claim 1 , wherein the brake is selectively operable to disengage from the second input, so that the second input is not braked by the brake.

13 . The air pressurisation system of claim 1 , wherein the system further comprises a further brake coupled to the second input, wherein the further brake is operable to engage and brake the transmission at the second input, in order to fix a transmission ratio of the transmission between the first input and the output.

14 . The air pressurisation system of claim 13 , wherein the brake is configured to engage and brake the transmission at the second input when a speed of the transmission at the second input exceeds a predetermined threshold speed, and wherein the further brake is selectively operable to brake the transmission at the second input.

15 . A gas turbine engine comprising the air pressurisation system of claim 1 .

16 . An aircraft comprising an airframe, a gas turbine engine and the air pressurisation system of claim 1 .

Assignees

• Rolls Royce Plc

Inventors

• Murray Christopher A

Classifications

• F16H2200/2033

  with one engaging means · CPC title

• F16H2200/2005

  with one sets of orbital gears · CPC title

• F16H3/72

  with a secondary drive, e.g. regulating motor, in order to vary speed continuously · CPC title

• F05D2260/40311

  of the epicyclical, planetary or differential type · CPC title

• F02C7/32

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