Gas turbine engine with gearbox health features

Patent metadata

Field	Value
Publication number	US-10107135-B2
Application number	US-201514922507-A
Country	US
Kind code	B2
Filing date	Oct 26, 2015
Priority date	Oct 26, 2015
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

A gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, a fan and a braking system. The braking system is configured to selectively engage the fan during ground windmilling to apply a first level of braking to slow rotation of the fan. Further, when the rotation of the fan sufficiently slows, the braking system is further configured to apply a second level of braking more restrictive than the first level of braking.

First claim

The invention claimed is:

1. A gas turbine engine, comprising:
a fan; and
a braking system configured to selectively engage the fan during ground windmilling to apply a first level of braking to slow rotation of the fan and, when the rotation of the fan slows, apply a second level of braking more restrictive than the first level of braking;
wherein the braking system includes a brake, and wherein the fan includes a disc, the brake configured to selectively engage the disc to apply the first level of braking to slow rotation of the fan, and
wherein the braking system further includes a pawl, and wherein the disc includes a slot, the pawl configured to selectively engage the slot to apply the second level of braking and to substantially lock the fan against rotation.

2. The gas turbine engine as recited in claim 1 , further comprising a gear reduction between the fan and a shaft of the engine.

3. The gas turbine engine as recited in claim 1 , wherein the brake engages the disc following an engine shut-off event and slows the rotation of the fan, and, when the rotation of the fan sufficiently slows, the pawl engages the slot to lock the fan against further rotation.

4. The gas turbine engine as recited in claim 1 , wherein the pawl is biased into engagement with the slot, and wherein the pawl is selectively retracted from the slot by an actuator.

5. The gas turbine engine as recited in claim 1 , wherein, when deployed during an in-flight condition, the pawl and brake are designed to either shear or wear away.

Assignees

• United Technologies Corp

Inventors

• Schwarz Frederick M
• Sheridan William G

Classifications

• Y02T50/60

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

• F05D2270/3032

  excessive temperatures, e.g. caused by overheating · CPC title

• F05D2270/301

  Pressure · CPC title

• F05D2270/116

  by preventing reverse rotation · CPC title

• F05D2260/311

  of the frangible or shear type · CPC title