Gearbox planet attenuation spring damper

Patent metadata

Field	Value
Publication number	US-9677659-B1
Application number	US-201615008986-A
Country	US
Kind code	B1
Filing date	Jan 28, 2016
Priority date	Jan 28, 2016
Publication date	Jun 13, 2017
Grant date	Jun 13, 2017

Abstract

An epicyclic gearing arrangement includes a planet gear rotatable on a planet bearing that is mounted via a support pin to a carrier of the epicyclic gearing arrangement. An attenuation spring is disposed between the outer surface of the bearing's outer ring and the opposing inner surface of the planet gear and includes an annular gap. A spring film damper is disposed between the cylindrical outer surface of the support pin and the opposing inner surface of the inner ring of the planet bearing and includes an annular gap. The support pin ( 96 ) and/or outer ring include oil feed holes that open into the respective annular gap(s). A gas turbine engine includes an epicyclic gearing arrangement having such a planet bearing.

First claim

What is claimed is:

1. A planet gearbox for connection to a carrier of an epicyclic gearing arrangement that has only a single input and a single output and that includes a sun gear and a ring gear surrounding the planet gearbox and the sun gear, the planet gearbox comprising:
a support pin is configured to be fixed to the carrier, the support pin is a hollow body that is defined by a cylindrical outer surface that is radially equidistant from a virtual central axis that extends in an axial direction, the support pin is further defined by an inner surface disposed opposite the cylindrical outer surface;
an inner ring is non-rotatably connected to the support pin and defines an inner surface opposed to the outer surface of the support pin, the inner ring defining an outer surface that defines at least one track, each track defined in the outer surface being configured to receive and rotatably guide therein a respective plurality of cylindrical rollers;
an outer ring defines an inner cylindrical surface that is disposed facing toward the at least one track, the outer ring defining an outer cylindrical surface that is disposed facing toward the ring gear;
a respective plurality of cylindrical rollers rotatably disposed within each respective track of the inner ring, and each of the plurality of rollers rotatably contacting the inner cylindrical surface of the outer ring; and
a planet gear is non-rotatably connected to the outer ring and defines an inner surface opposed to the outer surface of the outer ring, the planet gear defining an outer surface that defines a gear tooth surface that is configured to mesh with both the sun gear and the ring gear; and
an attenuation spring disposed between the outer surface of the outer ring and the inner surface of the planet gear.

2. The planet gearbox of claim 1 , wherein the planet gear is non-rotatably connected to the outer ring by welding.

3. The planet gearbox of claim 1 , wherein the planet gear is non-rotatably connected to the outer ring by mechanical fasteners.

4. The planet gearbox of claim 3 , wherein the mechanical fasteners that non-rotatably connect the planet gear to the outer ring include a spring finger housing.

5. The planet gearbox of claim 1 , wherein an annular gap extends between the cylindrical outer surface of the outer ring and the inner surface of the planet gear and the attenuation spring is disposed in the annular gap.

6. The planet gearbox of claim 5 , wherein the dimension of the annular gap depends upon the degree of compression of the attenuation spring.

7. The planet gearbox of claim 1 , further comprising a squeeze film damper that includes an annular gap that is defined between the cylindrical outer surface of the support pin and the inner surface of the inner ring.

8. The planet gearbox of claim 7 , wherein the squeeze film damper includes a resilient forward toroidal seal at a forward end of the annular gap and a resilient aft toroidal seal at an aft end of the annular gap.

9. The planet gearbox of claim 7 , wherein the support pin includes at least a first oil feed hole extending through the support pin between the inner surface and the outer surface of the support pin and defining an exit opening at the outer surface of the support pin, wherein the exit opening of the first oil feed hole is disposed in fluid communication with the annular gap.

10. The planet gearbox of claim 7 , wherein the support pin includes at least a first oil feed hole extending through the support pin between the inner surface and the outer surface of the support pin and defining an exit opening at the outer surface of the support pin, wherein the exit opening of the first oil feed hole is disposed in fluid communication with the squeeze film damper.

11. The planet gearbox of claim 7 , wherein the inner ring is defined by a forward end and an aft end that is spaced axially apart from the forward end, the squeeze film damper includes a forward groove defined in the forward end of the inner ring and extending circumferentially with respect to the virtual central axis.

12. The planet gearbox of claim 11 , wherein the forward groove of the inner ring defines a radial depth that extends from the inner surface of the inner ring in a direction radially away from the virtual central axis, and the squeeze film damper further includes a forward resilient seal disposed within the forward groove of the inner ring, the forward resilient seal defining an inner diameter and an outer diameter that is larger than the inner diameter such that the difference between the inner diameter and the outer diameter defines the uncompressed thickness of the forward resilient seal, and the uncompressed thickness of the forward resilient seal is greater than the radial depth of the forward groove of the inner ring.

13. The planet gearbox of claim 12 , wherein the squeeze film damper includes an aft groove defined in the aft end of the inner ring and extending circumferentially with respect to the virtual central axis, the aft groove defines a radial depth that extends from the inner surface of the inner ring in a direction radially away from the virtual central axis, and the squeeze film damper further includes an aft resilient seal disposed within the aft groove of the inner ring, the aft resilient seal defining an inner diameter and an outer diameter that is larger than the inner diameter such that the difference between the inner diameter and the outer diameter of the aft resilient seal defines the uncompressed thickness of the aft resilient seal, and the uncompressed thickness of the aft resilient seal is greater than the radial depth of the aft groove of the inner ring.

14. A gas turbine engine comprising:
a fan including a plurality of blades extending radially from a hub and rotatable about a first axis of rotation defined centrally through the hub;
a compressor disposed downstream from the fan;
a turbine disposed downstream of the compressor;
a rotatable input shaft mechanically coupling the compressor to rotate in unison with the turbine;
an epicyclic gearing arrangement that has only a single input and that includes a carrier, a sun gear rotatable about a second axis of rotation that is parallel to the first axis of rotation, a ring gear disposed circumferentially around the sun gear, at least one planet gearbox that is carried by the carrier and houses a planet gear rotatable with respect to the carrier about a third axis of rotation that is parallel to the second axis of rotation, wherein the at least one planet gear meshes with both the sun gear and the ring gear; and
an engine envelope surrounding the fan, the compressor, the turbine and the epicyclic gearing arrangement, wherein one of the ring gear and the carrier is non-rotatably coupled to the engine envelope; and
the planet gearbox further including:
a support pin is configured to be fixed to the carrier, the support pin is a hollow body that is defined by a cylindrical outer surface that is radially equidistant from a virtual central axis that extends in an axial direction, the support pin is further defined by an inner surface disposed opposite the cylindrical outer surface;
an inner ring is non-rotatably connected to the support pin and defines an inner surface opposed to the outer surface of the support pin, the inner ring defining an outer surface that defines at least one track, each track defined in the outer surface being configured to receive and rotatably guide therein a respective plurality of cylindrical rollers;
an outer ring defines an inner cylindrical surface that is disposed facing toward the at least one track, the outer ring defini

Assignees

• Gen Electric

Inventors

• Niergarth Daniel Alan
• Miller Brandon Wayne
• Ertas Bugra Han
• Bradley Donald Albert
• Dickman Joseph Robert

Classifications

• F16H2057/085

  Bearings for orbital gears · CPC title

• F05D2260/40311

  of the epicyclical, planetary or differential type · CPC title

• F16H57/082

  Planet carriers · CPC title

• F16H57/028

  characterised by means for reducing vibration or noise · CPC title

• F16C2360/23

  Gas turbine engines · CPC title