atc idea

I have uploaded this idea due to the fact without any equipment or tools so i cannot make any sort of prototype, I would like to have others input and thoughts in the design.

The idea came from work we have a machine that takes a screw in sleeve to attach a nylon cylinder to. When you pull the handle the sleeve pushes out too a slightly bigger to take the diameter of the nylon cylinder. When it shuts the sleeve is pulled back into a collar, which then it compresses the sleeve due to the collar only making its way the the very edge of the inner sleeve to grip the nylon cylinder

What is needed to just to finish the 3d design, is that i'm struggling to make a spring that will fit in between the collar and the inner tool sleeve, then a lid to stop the spring from coming out under compression.

The hole i made was to fit a 5 mm mill bit so i made the hole 6mm and made the slits 1 mm, I also tried to calculate the radius for the collar and how far down it would go to close the gap.