Very interesting.
Look at that illustration in the link above. Take a good look at the inset enlargement.
Does that remind anyone something?
Come on...
It looks like the actuator for an electric bell. In fact substitute the 'belt' with a flat metal and you got an armature for an electric bell/buzzer.
It is one of those '*SLAP !* Why didn't I think of that!' moments.
Very nice, very inventive.
Bravo !
