Fastening device in safety ski bindings

Claim 1

A SAFETY SKI BINDING COMPRISING, IN COMBINATION SUPPORT MEANS ADAPTED TO BE MOUNTED ON THE TOP SURFACE OF A SKI; A SKI BOOT HOLDING DEVICE MOUNTED ON SAID SUPPORT MEANS FOR TURNING ABOUT AN AXIS, SAID HOLDING DEVICE HAVING A LONGIGUDINAL AXIS EXTENDING LONGITUDINALLY ON THE SKI; CAM SURFACE MEANS, A ROLLER MEANS, AND SPRING MEANS, ALL INTERPOSED BETWEEN SAID SUPPORT MEANS AND SAID HOLDING DEVICE; SAID ROLLER MEANS BEING OPERATIVELY ENGAGED WITH SAID CAM SURFACE MEANS AND SAID SPRING MEANS MAINTAINING SAID ROLLER MEANS AND SAID CAM SURFACE MEANS IN OPERATIVE ENGAGEMENT; SAID SPRING MEANS BEING MOUNTED ON ONE OF SAID SUPPORT MEANS AND SAID HOLDING DEVICE, AND SAID CAM SURFACE MEANS BEING MOUNTED ON THE OTHER OF SAID SUPPORT MEANS AND SAID HOLDING DEVICE; SAID HOLDING DEVICE SWINGING ABOUT ITS TURNING AXIS, WHEN EXCESSIVE PRESSURE IS APPLIED AGAINST THE SKI BOOT, TO RELEASE THE LATTER; SAID CAM SURFACE MEANS INCLUDING A PAIR OF SIMILAR AND OPPOSITELY EXTENDING CAM SURFACES, THE INNER ENDS OF SAID CAM SURFACES CONJOINTLY DEFINING A RELATIVELY DEEP RECESS CENTERED ON THE LONGITUDINAL AXIS OF SAID HOLDING MEANS; EACH CAM SURFACE INCLUDING A FIRST SURFACE PORTION EXTENDING FROM SAID RECESS AND A SECOND SURFACE PORTION EXTENDING FROM SAID FIRST SURFACE PORTION; SAID FIRST SURFACE PORTION BEING INCLINED AT A RELATIVELY SMALL ANGLE RELATIVE TO THE DIRECTION OF ACTION OF SAID SPRING MEANS, AND SAID SECOND SURFACE PORTION BEING INCLINED AT A SHARPLY LARGE ANGLE RELATIVE TO THE DIRECTION OF ACTION OF SAID SPRING MEANS; WHEREBY THE EFFECTIVE FORCE OF THE SPRING MEANS IS SUBSTANTIALLY CONSTANT IN THEN RANGE OF SMALLER MOVEMENTS OF SAID HOLDING DEVICE RELATIVE TO ITS NORMAL OPERATING POSITION, AND SAID SPRING MEANS, IN THE RANGE OF LARGER MOVEMENTS OF SAID HOLDING DEVICE RELATIVE TO ITS NORMAL OPERATIVE POSITION, HAVING A SUBSTANTIALLY CONSTANT EFFECTIVE FORCE WHICH RANGES FROM A MINOR FRACTION OF THE EFECTIVE FORCE IN THE RANGE OF SMALLER MOVEMENTS OF SAID HOLDING DEVICE TO ZERO.