Automatic adjusting devices for brakes, clutches and the like

Claim 1

A DISC BRAKE COMPRISING A ROTATABLE AXIALLY MOVABLE DISC, A FIXED FRICTION ELEMENT ON ONE SIDE OF SAID DISC, AN AXIALLY MOVABLE FRICTION ELEMENT ON THE OTHER SIDE OF SAID DISC AXIALLY ALIGNED WITH SAID FIXED FRICTION ELEMENT, A SUPPORTING STRUCTURE ADJACENT SAID DISC ON WHICH SAID FIXED FRICTION ELEMENT IS MOUNTED ON ONE SIDE OF SAID DISC AND COMPRISING A GUIDE ON THE OPPOSITE SIDE OF SAID DISC IN WHICH SAID MOVABLE FRICTION ELEMENT IS MOUNTED TO MOVE AXIALLY INTO AND OUT OF FRICTIONAL ENGAGEMENT WITH SAID DISC, A NUT ROTATABLY MOUNTED IN FIXED AXIAL POSITION ON SAID SUPPORTING STRUCTURE, A NON-ROTATABLE, AXIALLY MOVABLE, THREADED MEMBER HAVING SCREW THREADS ENGAGING THE THREADS OF SAID NUT AND MOVABLE AXIALLY ON ROTATION OF SAID NUT, A THRUST MEMBER INTEGRAL WITH SAID THREADED MEMBER AND AXIALLY ALIGNED WITH SAID FRICTION ELEMENTS, A BRAKE OPERATING LEVER PIVOTALLY MOUNTED BETWEEN SAID THRUST MEMBER AND SAID MOVABLE FRICTION ELEMENT MOUNTED IN SAID GUIDES, THE OPPOSED FACES OF SAID LEVER AND THRUST MEMBER HAVING OPPOSED RAMPED RECESSES, BALLS LOCATED BETWEEN SAID RAMPED RECESSES WHEREBY ANGULAR MOVEMENT OF THE LEVER IN ONE DIRECTION CAUSES AXIAL MOVEMENT OF SAID MOVABLE FRICTION ELEMENT TO FRICTIONAL ENGAGEMENT WITH SAID DISC, A RETRACTION MECHANISM ON SAID SUPPORTING STRUCTURE TO WITHDRAW SAID MOVABLE FRICTION ELEMENT A LIMITED DISTANCE FROM SAID DISC UPON RETURN OF SAID LEVER FROM BRAKE APPLYING POSITION, AND SPRING MEANS MOUNTED AT ONE END ON SAID SUPPORTING STRUCTURE AND CONNECTED AT ITS OPPOSITE END TO SAID NUT TO ROTATE SAID NUT IN A DIRECTION TO ADVANCE SAID THRUST MEMBER PROGRESSIVELY TOWARD SAID FRICTION ELEMENT ON THE RETURN STROKE OF SAID LEVER AS SAID FRICTION PADS WEAR.