Variable pulley system

Claim 1

AN ADJUSTABLE WIDTH DRIVE PULLEY COMPRISING A TAPER LOCK BUSHING ASSEMBLY ADAPTED TO BE SECURED FIXEDLY AND SYMMETRICALLY TO A SHAFT, SAID BUSHING ASSEMBLY BEING ELONGATED AXIALLY OF THE SHAFT ON WHICH IT MOUNTS AND COMPRISING AN EXTERNAL CYLINDRICAL LOCATING SURFACE AND A SPLINED DRIVE PORTION SPACED AXIALLY FROM SAID LOCATING SURFACE, A FIRST SHEAVE PART HAVING AN ELONGATED SLEEVE PROVIDED INTERNALLY AT ONE END WITH A CYLINDRICAL LOCATING SURFACE SLIDABLE ON THE LOCATING SURFACE OF SAID BUSHING ASSEMBLY AND AT THE OPPOSITE END WITH A SPLINED DRIVE PORTION ENGAGED WITH AND SLIDABLE ON THE SPLINED DRIVE PORTION OF SAID BRUSHING AND PROVIDED EXTERNALLY WITH AN AXIALLY SPACED CYLINDRICAL LOCATING SURFACE AND A SPLINED DRIVING PORTION AND A CONICALLY INCLINED BELT-ENGAGING FLANGE AT ONE END OF SAID SLEEVE; A SECOND SHEAVE PART HAVING AN ELONGATED SLEEVE PROVIDED INTERNALLY WITH A CYLINDRICAL LOCATING SURFACE SLIDABLE AXIALLY ON THE LOCATING SURFACE PROVIDED EXTERNALLY ON SAID FIRST SHEAVE PART AND A SPLINED DRIVE PORTION ENGAGED WITH SAID SLIDABLE ON THE SPLINED DRIVE PORTION PROVIDED EXTERNALLY ON SAID FIRST SHEAVE PART, AND AN OPPOSITELY INCLINED CONICAL BELT-ENGAGING FLANGE AT ONE END OF THE SLEEVE ON SAID SECOND SHEAVE PART, SAID FLANGES BEING AT CORRESPONDING ENDS OF SAID SLEEVES, AND TOGETHER DEFINING A PULLEY FOR USE WITH A BELT HAVING INCLINED EDGES; AND MEANS FOR PROVIDING OPPOSITE MOVEMENT OF SAID SHEAVE PARTS RELATIVE TO SAID BUSHING ASSEMBLY COMPRISING A SCREW SHAFT HAVING OPPOSITE HAND THREADED PORTIONS, SAID SHAFT BEING COAXIAL WITH SAID DRIVE SHAFT AND EXTENDING INTO BOTH OF SAID SLEEVES, NUTS ON SAID SHAFT PORTIONS, THRUST BEARINGS CONNECTING EACH OF SAID NUTS TO ONE OF SAID SLEEVES, MEANS FOR PREVENTING ROTATION OF SAID NUTS, AND MEANS FOR ROTATING SAID SCREW SHAFT TO MOVE SAID SHEAVE PARTS AXIALLY IN OPPOSITE DIRECTIONS.