Magnetic variable torque clutch

Claim 1

AN ELECTRO-MECHANICAL CLUTCH COMPRISING: (A) OUTPUT SHAFT ROTATABLE MOUNTED AT A FIXED POSITION ALONG A PREDETERMINED AXIS, SAID OUTPUT SHAFT BEING PROVIDED WITH A DISC PROVIDING A SURFACE OF REVOLUTION ABOUT SAID SHAFT; (B) AN ELEMENT ROTATABLY MOUNTED ABOUT SAID SHAFT WITH AN AXIS OF ROTATION ALONG SAID PREDETERMINED AXIS, SAID ELEMENT HAVING AN INNER SURFACE IN A PARALLEL PLANE SPACED FROM SAID SURFACE OF REVOLUTION OF SAID DISC AND HAVING A PORTION THEREOF ON THE OPPOSITE SIDE OF SAID SURFACE OF REVOLUTION OF SAID DISC COMPOSED OF MATERIAL OF PERMEABILITY GREATER THAN UNITY; (C) MEANS INCLUDING A PERMANENT MAGNET ATTACHED TO SAID DISC ON THE SIDE THEREOF OPPOSITE FROM SAID SURFACE OF REVOLUTION FOR GENERATING A FIRST MAGNETIC FIELD IN A PREDETERMINED DIRECTION THROUGH SAID PORTION OF SAID ELEMENT THEREBY TO NORMALLY MAINTAIN SAID INNER SURFACE OF SAID ELEMENT SPACED FROM SAID SURFACE OF REVOLUTION OF SAID DISC;