Oi, some weeks ago I came up with this, cuz I read somewhere around here that having tension both in the top and bottom was a good idea.
I designed it for a 40mm papaiz padlock, but found out that it didn´t work because of the shackle-spring, no wait a minute not that one the other one, what is it called? the two springs in the topmiddle keeping the shackle from poping!
It works well with eurocylinder, cuz the have no springs.
I tryed to make it so that the energy goes to, both top and bottom when pushing.
I push down on the right side according to the lowest pic.
It works, but let´s just call it a prototype!
It works best if you attach a rubberband, (making it handsfree, which is cool) given it medium light tension, to the place where you would put you finger, and the other end you attach to the screw above the doorknob, which you unscrew just a little, and if there ain´t one, well you´ll think of something.
Alright, I know that I said that I pushed down, but I attach the rubberband on the top screw, how is that, well it´s because the cylinder is turned upside down, here in Brazil, alot of times anyway.(see first pic. for ref., the name of the lock is alianca)
That just about covers what I want so say, have a nice day!