Friction couple cooling device

Claim 1

A ROTARY FRICTION DISC FOR A FLUID COOLED FRICTION COUPLE OF THE KIND WHICH COOLING FLUID IS CIRCULATED THROUGH A STACK OF ENGAGED, RELATIVELY ROTATABLE FRICTION DISCS TO PREVENT OVERHEATING OF THE DISCS, SAID DISC COMPRISING AN ANNULAR METAL PLATE FORMED WITH SPLINES ABOUT ONE PERIPHERY, A SINTERED METALLIC FRICTION FACING BONDED OF EACH FACE OF THE PLATE AND EXTENDING ACROSS SUBSTANTIALLY THE ENTIRE RADIAL EXTENT OF THE PLATE FROM THE SPLINES TO THE OTHER PERIPHERY FOR MINIMIZING DIFFERENCES IN THERMAL EXPANSION BETWEEN THE INNER AND OUTER PORTIONS OF THE PLATE, EACH OF SAID FACINGS HAVING GENERALLY CIRCUMFERENTIAL GROOVES FORMED THEREIN ACROSS THE ENTIRE RADIAL EXTENT OF THE FACING, SAID CIRCUMFERENTIAL GROOVES BEING MULTIPLE LEAD SPIRAL GROOVES, EACH OF SAID FACINGS ALSO HAVING GENERALLY RADIALLY EXTENDING GROOVES FORMED THEREIN AT SUBSTANTIALLY EQUAL INTERVALS ABOUT THE CIRCUMFERENCE OF THE FACING WITH EACH RADIAL GROOVE IN ONE FACING DISPOSED BETWEEN TWO RADIAL GROOVES IN THE OTHER FACING, THE RADIAL GROOVES BEING FORMED AS A FIRST AND SECOND SET OF PARALLEL PAIRS, EACH PAIR IN EACH SET BEING DISPOSED AT 45* WITH RESPECT TO AN ADJACENT PAIR IN THE SET, AND THE TWO SETS BEING CIRCUMFERENTIALLY OFFSET SUFFICIENT TO POSITION ONE GROOVE OF EACH PAIR IN THE SECOND SET SUBSTANTIALLY MIDWAY BETWEEN A PARALLEL PAIR OF GROOVES IN THE FIRST SET, AND RADIAL SLOTS EXTENDING INWARDLY FROM THE OUTER PERIPHERY THROUGH BOTH THE FACINGS AND THE METAL PLATE AND TERMINATING IN A SLIGHTLY ENLARGED CIRCULAR OPENING DISPOSED IN THE INNER ANNULAR PORTION OF THE FRICTION DISC TO ACCOMMODATE CIRCUMFERENTIAL EXPANSION OF THE OUTER PERIPHERAL PORTION OF THE FRICTION DISC.