How to design self-reversing screws?

[RubenJ]

good afternoon
I would like to design a self-reversing screws for a small personal project, but I can not find anything to be able to carry it out, as well as measurements, thread pitch, gypsi, ...
to see if you can help me

 

[berkeman]

Welcome to the PF, Ruben.

but I can not find anything to be able to carry it out,

A google search turns up all kinds of information. Have you looked through the search results yet? Can you say more about the application?

https://www.google.com/search?q=self-reversing+screw+design&ie=utf-8&oe=utf-8&client=firefox-b-1

 

[RubenJ]

Hello
I've searched on the subject in Google but I can not find anything about the development and calculations. As well as the size of the gypsi on the axis of the self-reversing screws. I would like to develop one for a biomass feeding system, it is a personal project, but I really do not find anything.
Thank you.