Gearbox assembly
View Patent ↗A gearbox assembly includes a plurality of planet gears. At least one planet gear of the plurality of planet gears includes a layshaft that supports a first stage planet gear and a second stage planet gear. The at least one planet gear is characterized by a Radial Stage Distance greater than or equal to 30 millimeters and less than or equal to 100 millimeters. The Radial Stage Distance is R rm1 −R rt2 . R rm1 is a first stage rim inner radius of the first stage planet gear and R rt2 is a second stage root radius of the second stage planet gear.
1. A gearbox assembly comprising:
a plurality of planet gears, at least one planet gear of the plurality of planet gears including:
a layshaft that supports a first stage planet gear and a second stage planet gear, the at least one planet gear being characterized by a Radial Stage Distance greater than or equal to 30 millimeters and less than or equal to 100 millimeters, the Radial Stage Distance being R rm1 −R rt2 , wherein R rm1 is a first stage rim inner radius of the first stage planet gear and R rt2 is a second stage root radius of the second stage planet gear; and
a rim of the second stage planet gear that defines a rim thickness, wherein a radial force acts on the rim during operation of the gearbox assembly, and a ratio of the radial force on the rim to the rim thickness is greater than or equal to 3 kilonewtons per millimeter and less than or equal to 9 kilonewtons per millimeter.
2. The gearbox assembly of claim 1 , wherein R rm1 is greater than or equal to 90 millimeters and less than or equal to 270 millimeters.
3. The gearbox assembly of claim 1 , wherein R rt2 is greater than or equal to 60 millimeters and less than or equal to 170 millimeters.
4. The gearbox assembly of claim 1 , wherein the rim is the rim of the second stage planet gear.
5. The gearbox assembly of claim 4 , wherein the second stage planet gear includes a radially inner surface and a root, and the rim thickness is defined from the radially inner surface to the root.
6. The gearbox assembly of claim 5 , wherein the rim thickness is greater than or equal to 10 millimeters and less than or equal to 40 millimeters.
7. The gearbox assembly of claim 1 , wherein the layshaft has a volume of material, and the volume is greater than or equal to 3 cubic decimeters and less than or equal to 20 cubic decimeters.
8. The gearbox assembly of claim 1 , further including a roller bearing disposed within the at least one planet gear, the roller bearing having a roller bearing radius that is greater than or equal to 50 millimeters and less than or equal to 140 millimeters.
9. The gearbox assembly of claim 1 , wherein an axial length of the layshaft is greater than or equal to 150 millimeters and less than or equal to 300 millimeters.
10. The gearbox assembly of claim 1 , wherein an axial distance between the first stage planet gear and the second stage planet gear is greater than or equal to 1 millimeter and less than or equal to 6 millimeters.
11. A turbine engine comprising:
a core turbine engine coupled to an input shaft;
a fan coupled to an output shaft; and
a gearbox assembly, wherein a torque is transferrable from the input shaft to the output shaft through the gearbox assembly, the gearbox assembly comprising:
a plurality of planet gears, at least one planet gear of the plurality of planet gears including:
a layshaft that supports a first stage planet gear and a second stage planet gear, the at least one planet gear being characterized by a Radial Stage Distance greater than or equal to 30 millimeters and less than or equal to 100 millimeters, the Radial Stage Distance being R rm1 −R rt2 , wherein R rm1 is a first stage rim inner radius of the first stage planet gear and R rt2 is a second stage root radius of the second stage planet gear; and
a rim of the second stage planet gear that defines a rim thickness, wherein a radial force acts on the rim during operation of the gearbox assembly, and a ratio of the radial force on the rim to the rim thickness is greater than or equal to 3 kilonewtons per millimeter and less than or equal to 9 kilonewtons per millimeter.
12. The turbine engine of claim 11 , wherein R rm1 is greater than or equal to 90 millimeters and less than or equal to 270 millimeters.
13. The turbine engine of claim 11 , wherein R rt2 is greater than or equal to 60 millimeters and less than or equal to 170 millimeters.
14. The turbine engine of claim 11 , wherein the rim is the rim of the second stage planet gear.
15. The turbine engine of claim 14 , wherein the second stage planet gear includes a radially inner surface and a root, and the rim thickness is defined from the radially inner surface to the root.
16. The turbine engine of claim 15 , wherein the rim thickness is greater than or equal to 10 millimeters and less than or equal to 40 millimeters.
17. The turbine engine of claim 11 , wherein the layshaft has a volume of material, and the volume is greater than or equal to 3 cubic decimeters and less than or equal to 20 cubic decimeters.
18. The turbine engine of claim 11 , further including a roller bearing disposed within the at least one planet gear, the roller bearing having a roller bearing radius that is greater than or equal to 50 millimeters and less than or equal to 140 millimeters.
19. The turbine engine of claim 11 , wherein an axial length of the layshaft is greater than or equal to 150 millimeters and less than or equal to 300 millimeters.
20. The turbine engine of claim 11 , wherein an axial distance between the first stage planet gear and the second stage planet gear is greater than or equal to 1 millimeter and less than or equal to 6 millimeters.