[Fichori]

I would speculate that the magnetism pulls the rotor around much in the same fashion that expanding gases or air would push it around.

I'm afraid I'll have to see better drawings before I even start to understand it.

Here's something I can understand...
(Blue-green object on the right is a valve)

(Untested idea for firing pellets with compressed air in a center fire rifle.)

[incredulous joe]

That looks like a spud gun.