Gearbox with sealed accessory vent

Patent metadata

Field	Value
Publication number	US-2016160992-A1
Application number	US-201514940269-A
Country	US
Kind code	A1
Filing date	Nov 13, 2015
Priority date	Dec 8, 2014
Publication date	Jun 9, 2016
Grant date	—

Abstract

A gearbox vent apparatus includes: a gearbox; an accessory contained in a case mounted to the gearbox such than an interior space of the case communicates with an interior space of the gearbox, wherein the case includes a sidewall and an endwall, a hollow drive shaft mounted for rotation inside the case; an annular first seal element mounted to the drive shaft; an annular second seal element mounted to the case and contacting the first seal element so as to define a sealing interface; and a vent tube having a forward end coupled to the endwall in fluid communication with the drive shaft.

First claim

What is claimed is:

1 . A gearbox vent apparatus comprising:
a gearbox; an accessory contained in a case mounted to the gearbox such than an interior space of the case communicates with an interior space of the gearbox, wherein the case includes a sidewall and an endwall, a hollow drive shaft mounted for rotation inside the case; an annular first seal element mounted to the drive shaft; an annular second seal element mounted to the case and contacting the first seal element so as to define a sealing interface; and a vent tube having a forward end coupled to the endwall in fluid communication with the drive shaft.

2 . The apparatus of claim 1 wherein the stator includes at least one drain channel formed therein, interconnecting the interior spaces of the case and the gearbox.

3 . The apparatus of claim 1 wherein the accessory is an alternator including an annular rotor mounted to the drive shaft, surrounded by an annular stator mounted in the case.

4 . The apparatus of claim 1 wherein the sidewall of the case incorporates an oil nozzle oriented to discharge oil radially inward into the interior space of the case, towards the first and second seal elements.

5 . The apparatus of claim 1 wherein the oil nozzle communicates with a channel in the case which in turn communicates with an oil gallery in the gearbox.

6 . The apparatus of claim 1 wherein the alternator is a permanent magnet alternator.

7 . The apparatus of claim 1 wherein the at least one drain channel in formed in the stator of the alternator.

8 . The apparatus of claim 1 wherein the rotor abuts a shoulder formed on an outer surface of the drive shaft and is retained in position against the rotor by a locking nut engaged with the drive shaft.

9 . The apparatus of claim 1 wherein at least one of the first and second seal elements comprises carbon graphite material.

10 . The apparatus of claim 9 wherein the second seal element comprises carbon graphite material and the first seal element is a different material.

11 . The apparatus of claim 1 wherein an overboard tube is coupled to an aft end of the vent tube.

12 . A gas turbine engine in combination with the gearbox vent apparatus of claim 1 , wherein the gearbox vent apparatus is mounted to a lower portion of the engine.

13 . The gas turbine engine of claim 11 further including an air-oil separator connected in fluid communication with the hollow drive shaft.

14 . The gas turbine engine of claim 12 further including an overboard tube coupled to an aft end of the vent tube.

15 . The gas turbine engine of claim 14 , wherein the overboard tube extends towards a centerline axis of the engine.

Assignees

• Gen Electric

Inventors

• Wotzak Mark Gregory
• Anstead Duane Howard
• Lukovic Bojan
• Luz James John
• Mc Carthy Thomas Charles
• Beatty Keith

Classifications

• F16H57/0456

  Lubrication by injection; Injection nozzles or tubes therefor (oil mist or spray lubrication F16H57/0458) · CPC title

• F16H57/029 Primary

  characterised by means for sealing the gearboxes, e.g. to improve airtightness · CPC title

• F05D2260/605

  Venting into the ambient atmosphere or the like · CPC title

• F02C7/32

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

• F16H57/0472

  Seals · CPC title