I have a square plate that I need t

[Michaelabba]

I have a square plate that I need to attach to round stock , I need to attach a spring to the flat plate so it returns from its 90deg rotation to the vertical static point.
I'm learning as I go.
I would like help/suggestions.

Thank you,
Michaelabba

 

[3DDave]

A sketch of the desired arrangement would help. Show it in both positions and which way gravity is being applied.