Epicyclic gear train

1. A gear apparatus, comprising:

an epicyclic gear train including 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, each journal bearing including an internal central cavity and at least one passage extending radially from the internal cavity to a peripheral journal surface of the respective journal bearing, wherein the epicyclic gear train has a gear reduction ratio of greater than or equal to about 2.3, the ring gear including an inner periphery with teeth, an outer circumferential surface opposite the teeth and a flange projecting radially outwards from the outer circumferential surface, the flange including an internal passage opening at the inner periphery and at a radially outer tip of the flange, the flange being secured with a seal and an oil guide in a joint.

2. The gear apparatus as recited in claim 1 , wherein the at least one passage includes a first passage and a second passage axially spaced from the first passage.

3. The gear apparatus as recited in claim 2 , wherein the internal cavity extends between axial ends, and the first passage and the second passage are non-uniformly spaced with regard to the axial ends.

4. The gear apparatus as recited in claim 1 , wherein the internal central cavity is axially blind.

5. The gear apparatus as recited in claim 1 , wherein the epicyclic gear train has a gear reduction ratio of greater than or equal to 2.3.

6. The gear apparatus as recited in claim 1 , wherein the epicyclic gear train has a gear reduction ratio of greater than or equal to about 2.5.

7. The gear apparatus as recited in claim 1 , wherein the epicyclic gear train has a gear reduction ratio of greater than or equal to 2.5.

8. The gear apparatus as recited in claim 1 , further comprising:

a gutter in contact with the seal and arranged about the opening at the radially outer tip of the flange, wherein the joint includes a slot there through that opens at one end to an interior area of the gutter and at another end to an area axially adjacent the ring gear.

9. The gear apparatus as recited in claim 8 , wherein the slot is located axially forward of the flange of the ring gear, and the joint includes a second slot there through located axially aft of the flange of the ring gear, the second slot opening at one end to the interior area of the gutter and at another end to an area axially aft of the ring gear.

10. A turbine engine comprising:

a turbine shaft;

a fan; and

an epicyclic gear train coupled between the turbine shaft and the fan, the epicyclic gear train including 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, each journal bearing including an internal central cavity and at least one passage extending radially from the internal cavity to a peripheral journal surface of the respective journal bearing, wherein the epicyclic gear train defines a gear reduction ratio of greater than or equal to about 2.3, the ring gear including an inner periphery with teeth, an outer circumferential surface opposite the teeth and a flange projecting radially outwards from the outer circumferential surface, the flange including an internal passage opening at the inner periphery and at a radially outer tip of the flange, the flange being secured with a seal and an oil guide in a joint.

11. The turbine engine as recited in claim 10 , wherein the at least one passage includes a first passage and a second passage axially spaced from the first passage.

12. The turbine engine as recited in claim 11 , wherein the internal cavity extends between axial ends, and the first passage and the second passage are non-uniformly spaced with regard to the axial ends.

13. The turbine engine as recited in claim 10 , wherein the internal central cavity is axially blind.

14. The turbine engine as recited in claim 10 , wherein the epicyclic gear train has a gear reduction ratio of greater than or equal to 2.3.

15. The turbine engine as recited in claim 10 , wherein the epicyclic gear train has a gear reduction ratio of greater than or equal to about 2.5.

16. The turbine engine as recited in claim 10 , wherein the epicyclic gear train has a gear reduction ratio of greater than or equal to 2.5.

17. The turbine engine as recited in claim 10 , wherein the fan defines a bypass ratio of greater than about ten (10) with regard to a bypass airflow and a core airflow.

18. The turbine engine as recited in claim 10 , wherein the fan defines a bypass ratio of greater than about 10.5:1 with regard to a bypass airflow and a core airflow.

19. The turbine engine as recited in claim 10 , wherein the fan defines a bypass ratio of greater than ten (10) with regard to a bypass airflow and a core airflow.

20. The turbine engine as recited in claim 10 , wherein the fan has a pressure ratio that is less than about 1.45.

21. The turbine engine as recited in claim 10 , wherein the fan has a pressure ratio that is that is less than 1.45.

22. The turbine engine as recited in claim 10 , further comprising:

a gutter in contact with the seal and arranged about the opening at the radially outer tip of the flange, wherein the joint includes a slot there through that opens at one end to an interior area of the gutter and at another end to an area axially adjacent the ring gear.

23. The turbine engine as recited in claim 22 , wherein the slot is located axially forward of the flange of the ring gear, and the joint includes a second slot there through located axially aft of the flange of the ring gear, the second slot opening at one end to the interior area of the gutter and at another end to an area axially aft of the ring gear.

24. A gear apparatus, comprising:

an epicyclic gear train including a carrier supporting intermediate gears that mesh with a sun gear, and a ring gear surrounding and meshing with the intermediate gears, each of the intermediate gears being supported on a respective bearing, the ring gear including an inner periphery with teeth, an outer circumferential surface opposite the teeth and a flange projecting radially outwards from the outer circumferential surface, the flange including an internal passage opening at the inner periphery and at a radially outer tip of the flange, the flange being secured with a seal and an oil guide in a joint; and

a gutter in contact with the seal and arranged about the opening at the radially outer tip of the flange, wherein the joint includes a slot there through that opens at one end to an interior area of the gutter and at another end to an area axially adjacent the ring gear.

25. A gas turbine engine comprising:

a turbine section comprising:

a first turbine section; and

a second turbine section, the second turbine section having a pressure ratio of greater than about 5.0;

a gear train configured to be driven the second turbine section, the gear train comprising:

a carrier supporting intermediate gears that mesh with a sun gear, and a ring gear surrounding and meshing with the intermediate gears, the ring gear comprising:

an inner periphery and an outer circumferential surface opposite the inner periphery; and

a flange projecting radially outwards from the outer circumferential surface, the flange including an internal passage opening at the inner periphery and at a radially outer tip of the flange, the flange being secured with a seal and an oil guide in a joint; and

a fan configured to be driven by the gear train at a speed lower than the speed of the second turbine section.

26. The gas turbine engine of claim 25 further comprising:

a compressor section; and

a bypass duct,

wherein the fan is configured to drive a first portion of air into the compressor and a second portion of air into the bypass duct, and

wherein a bypass ratio defined as the volume of area driven into the bypass duct divided by the volume of air driven into the compressor is greater than about 6.0.

27. The gas turbine engine of claim 26 , wherein the bypass ratio is greater than about 10.0.

28. The gas turbine engine of claim 25 , wherein a gear ratio of the gear train is greater than about 2.3.