# Thread: Help with Epicyclic Gearbox

1. ## Help with Epicyclic Gearbox

Got a problem I need a helping hand with, I'll give a brief summary first:

I'm designing a planetary gear train for a wind turbine, it is a step up gearbox
with a gearbox ratio 1:16, split into two stages, at 1:4 ratios each.

I need some help designing the dimensions of the annulus, planet and sun gears
(including number of teeth etc)

Using a planetary type set up, I have the following ratios:

Na/Ns = 3 (for both stages)

Np= (Na - Ns )/2 (for both stages)

(where Na = number of teeth on annulus, Ns = " " on sun, Np = " " on planets

***

I don't want anyone to solve this for me, I just want to be pointed in the right direction,
my lecturer said you work out the number of teeth etc based on the strength of the gear
and use equations to find it out, but i'm unsure as to what these equations could be?

Any ideas anyone?

I've got other information/properties if other people think i'll require them.

Thanks for any help

2. Your lecturer has already given you more than was necessary. He gave you the fundamental equations,Na/Ns = 3 (for both stages)Np= (Na - Ns )/2 (for both stages),and now it should be up to you to somehow get the sizing based on the loads.