SWISS PATENT OF THE 15th DECEMBER 1969
PIECE OF HOROLOGY WITH INTERNAL TURNING BEZEL.
Patent published the 31st of March 1973 under NO 535448
"The case-rim 3 is bearing an internal rim bounded with a ring 8 laid on an internal shoulder-piece of the case-rim 3 by taking an under-shoulder 3a of it, under which it is engaged at peg. An undulated lame-spring 9 interposed between the case-rim 3 and the ring 8 insures a friction of the turning bezel 7 to avoid untimely removal. (...). The arrangement is made in a manner that the rim rotation can only be made in the sense of diver's security and not in the reverse sense. So, whatever sense in which the steam 12 could be untimely manoeuvred while driving, there is no danger for the diver."