Ring gear mounting arrangement with oil scavenge scheme
A turbine engine includes an epicyclic gear train that has a two-piece ring gear. Each portion of the ring gear includes radially outwardly extending flanges that are axially constrained to a turbo fan shaft by bolts secured circumferentially along the flanges. Knife edge seals are secured to the flanges to contain oil expelled through the ring gear into a gutter. The ring gear and turbo fan shaft can be rotationally balanced together.
1. A gear support assembly for a turbine engine, comprising:
an epicyclic gear arrangement;
a first tapered bearing and a second tapered bearing spaced apart from the first tapered bearing, the first tapered bearing and the second tapered bearing being arranged axially forward of the epicyclic gear arrangement and supporting the epicyclic gear arrangement, wherein the first tapered bearing includes a first roller element defining a first rotational axis and the second tapered bearing includes a second roller element defining a second rotational axis such that the first rotational axis and the second rotational axis intersect at a position that is radially inwards from the first roller element and the second roller element.
2. The gear support assembly as recited in claim 1 , wherein the first tapered bearing and the second tapered bearing are located radially inwards from a radially outer surface of the epicyclic gear arrangement.
3. The gear support assembly as recited in claim 1 , wherein the first tapered bearing and the second tapered bearing are located radially outwards of a radially inner surface of the epicyclic gear arrangement.
4. The gear support assembly as recited in claim 1 , including a support arm extending forward from the epicyclic gear arrangement, at least one of the first tapered bearing and the second tapered bearing being mounted on the support arm.
5. The gear support assembly as recited in claim 4 , wherein the support arm is connected at one end at a radially outer location of the epicyclic gear arrangement.
6. The gear support assembly as recited in claim 1 , wherein at least one of the first tapered bearing and the second tapered bearing includes a cylindrical roller element.
7. The gear support assembly as recited in claim 6 , wherein the cylindrical roller element is supported on a tapered race.
8. The gear support assembly as recited in claim 1 , wherein the first tapered bearing and the second tapered bearing are spaced an equivalent radial distance from a central axis of the epicyclic gear arrangement.
9. The gear support assembly as recited in claim 1 , wherein the position at which the first rotational axis and the second rotational axis intersect is radially inwards from tapered inner races that support the first roller element and the second roller element.
10. The gear support assembly as recited in claim 1 , wherein the epicyclic gear arrangement includes a carrier supporting star gears that mesh with a sun gear, and a ring gear surrounding and meshing with the star gears, each of the star gears being supported on a respective journal bearing, the ring gear including first and second portions that abut at a radial interface, the first and second portions including an S-shaped outer circumferential surface.
11. The gear support assembly as recited in claim 10 , wherein the first and second portions have a first thickness T 1 that is less than a second thickness T 2 arranged axially inwardly from the first thickness T 1 .
12. A turbine engine comprising:
a compressor section;
a combustor arranged in fluid receiving communication with the compressor section;
a turbine section arranged in fluid receiving communication with the combustor;
an epicyclic gear arrangement coupled to be driven by the turbine section; and
a first tapered bearing and a second tapered bearing spaced apart from the first tapered bearing, the first tapered bearing and the second tapered bearing being arranged axially forward of the epicyclic gear arrangement and supporting the epicyclic gear arrangement.
13. The turbine engine as recited in claim 12 , including a fan located axially forward of the compressor section, wherein a forward one of the first tapered bearing and the second tapered bearing is located at an equivalent axial position of the fan.
14. The turbine engine as recited in claim 12 , including a fan located axially forward of the compressor section, wherein a forward one of the first tapered bearing and the second tapered bearing is located at an equivalent axial position of the fan and a rear one of the first tapered bearing and the second tapered bearing is located at a non-equivalent axial position of the fan.
15. The turbine engine as recited in claim 12 , wherein the first tapered bearing and the second tapered bearing are located radially inwards from a radially outer surface of the epicyclic gear arrangement.
16. The turbine engine as recited in claim 12 , including a support arm extending forward from the epicyclic gear arrangement, at least one of the first tapered bearing and the second tapered bearing being mounted on the support arm.
17. The turbine engine as recited in claim 16 , wherein the support arm is connected at one end at a radially outer location of the epicyclic gear arrangement.
18. The turbine engine as recited in claim 12 , wherein at least one of the first tapered bearing and the second tapered bearing includes a second cylindrical roller element.
19. The turbine engine as recited in claim 18 , wherein the cylindrical roller element is supported on a tapered race.
20. The turbine engine as recited in claim 12 , wherein the first tapered bearing and the second tapered bearing are spaced an equivalent radial distance from a central axis of the epicyclic gear arrangement.
21. The turbine engine as recited in claim 12 , wherein the first tapered bearing includes a first roller element defining a first rotational axis and the second tapered bearing includes a second roller element defining a second rotational axis such that the first rotational axis and the second rotational axis intersect at a position that is radially inwards from the first roller element and the second roller element.
22. The turbine engine as recited in claim 12 , wherein the epicyclic gear arrangement includes a carrier supporting star gears that mesh with a sun gear, and a ring gear surrounding and meshing with the star gears, each of the star gears being supported on a respective journal bearing, the ring gear including first and second portions that abut at a radial interface, the first and second portions including an S-shaped outer circumferential surface.
23. The turbine engine as recited in claim 22 , wherein the first and second portions have a first thickness T 1 that is less than a second thickness T 2 arranged axially inwardly from the first thickness T 1 .