Magnetic separator

Claim 1

IN A MAGNETIC SEPARATOR COMPRISING A CONVEYOR HAVING A MATERIAL RECEIVING SURFACE FOR CONVEYING MATERIALS TO BE SEPARATED AND A PERMANENT MAGNET ASSEMBLY HAVING THREE POLES AT A WORKING FACE THEREOF TO ATTRACT MAGNETIC MATERIAL TO BE SEPARATED TOWARDS SAID SURFACE, THE CONVEYOR BEING MOVABLE RELATIVE TO THE PERMANENT MAGNET ASSEMBLY, THE IMPROVEMENT COMPRISING FORMING SAID ASSEMBLY OF A UNITARY TROUGH-SHAPED YOKE COMPOSED SUBSTANTIALLY ENTIRELY OF PERMEABLE SOFT MAGNETIC MATERIAL HAVING TWO ENDS EXTENDING TO THE WORKING FACE OF THE MAGNETIC ASSEMBLY IN CLOSE PROXIMITY TO SAID SURFACE, A CENTRAL POLE MEMBER OF PERMEABLE SOFT MAGNETIC MATERIAL DISPOSED WITHIN SAID YOKE AND ATTACHED THERETO TO PROVIDE AN END TERMINATING AT THE WORKING FACE IN CLOSE PROXIMITY TO SAID SURFACE, A BODY OF ORIENTED PERMANENT MAGNETIC MATERIAL CONSISTING OF AT LEAST TWO STACKS OF CERAMIC PERMANENT MAGNETS IN SLAB FORM SUBSTANTIALLY COMPLETE FILLING THE SPACE WITHIN THE YOKE FROM THE WORKING FACE OF THE MAGNETIC ASSEMBLY, THE ARRANGEMENT AND DIRECTION OF MAGNETIZATION OF THE ORIENTED PERMANENT MAGNET MATERIAL BEING SUCH AS TO ESSENTIALLY CONVERGE ONE POLARITY THEREOF TOWARD THE CENTRAL POLE MEMBER AND THE OTHER POLARITY BEING DIRECTED TO THE TROUGHSHAPED YOKE, WHEREBY THE END OF THE CENTRAL POLE MEMBER HAS THE ONE POLARITY AND THE ENDS OF THE YOKE HAVE THE OTHER POLARITY.