planetary gear

Hello
I want to ask that is it possible to have the number of teeth of sun gear and pinion will be same?

As In my case the ratio is 4:1....outer ring is fixed and sun gear is the input. I want to use three planets.
and if I take 14,16,17 for the sun gear then the condition of (Z1 +Z3)/number of planets should be integer.
but if i take 15 for the sun gear then the number of teeth on planet is also 15 with 45 on ring.....

I want to ask is it right to take 15 teeth for both sun and planet and 45 for ring to get the ratio of 4:1????

Yes, that should work.

Sun = 15 teeth
Number of Planets = 3
Planet = 15 teeth
Ring = 45 teeth

Dave
Generally, I will not give you the answer to your question, but I [b]will[/b] guide you into discovering how to solve this yourself.
Insanity: "doing the same thing over and over again and expecting different results." Albert Einstein