Calculating the load on planetary gear from driving torque

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
2 replies · 5K views
Inneedofhelp
Hello,

I am very new to gears I am fairly confused about planetary gears. I want to know the load on the gears contact point between the sun and the planets and the planets and the ring, assuming the ring not moving. Given I have the solid works file ,the pressure angle, and the gear ratios, I can easily calculate the distances, teeth numbers, etc. I also know the initial driving torque of the sun gear.
So, my question is, utilizing the solid works file and the driving sun gear torque how do I calculate the load on the contact point for each of the gears? Is there a general equation I can use without knowing the power and the rpm?

Thank You
1.PNG
2.PNG
 
Last edited by a moderator:
Physics news on Phys.org
Your diagram omits the spider connection for the three planetary gears; but, of your question that is really irrelevant. The force on the three planetary gear's tooth and central input shaft gear tooth will be 1/3 x input torque x 1/2 x pitch diameter of the input shaft gear and will be same for both the inside and outside gear teeth on each planetary gear and on the ring gear teeth that does gears are contacting.