Slip limiting differential

Claim 1

A DRIVE MECHANISM COMPRISING ROTATABLE POWER INPUT MEANS, FIRST AND SECOND DRIVEN OUTPUT MEANS, DIFFERENTIAL GEAR MEANS FOR DRIVING SAID FIRST AND SECOND DRIVEN OUTPUT MEANS FOR SAID INPUT MEANS AND PROVIDING A DIFFERENTIAL ACTION BETWEEN SAID FIRST AND SECOND DRIVEN OUTPUT MEANS, SAID DIFFERENTIAL GEAR MEANS INCLUDING FIRST AND SECOND DIFFERENTIAL SIDE GEAR DRIVINGLY CONNECTED TO SAID FIRST AND SECOND DRIVEN OUTPUT MEANS TO EFFECT ROTATION OF SAID OUTPUT MEANS UPON ROTATION THEREOF AND A ROTATABLE PLANET CARRIER DRIVINGLY CONNECTED WITH SAID INPUT MEANS AND AT LEAST ONE PLANETARY GEAR ROTATABLY MOUNTED ON SAID PLANET CARRIER AND MESHING WITH SAID SIDE GEARS TO DRIVE THE SAME, AND ROLLER CLUTCH MEANS OPERABLE TO DRIVINGLY CONNECT SAID PLANET CARRIER TO ONE OF SAID SIDE GEARS AND INCLUDING A ROLLER CAGE MOVABLE TRANSVERSELY OF THE AXIS OF ROTATION OF SAID PLANET CARRIER AND OF SAID ONE OF SAID SIDE GEARS AND RELATIVE THERETO, DRIVE TRANSMITTING ROLLER ELEMENTS LOCATED IN SAID ROLLER CAGE AND BETWEEN RADIALLY SPACED DRIVE SURFACES ROTATABLE WITH SAID PLANET CARRIER AND SAID ONE OF SAID SIDE GEARS AND MOVABLE UPON MOVEMENT OF SAID ROLLER CAGE, SAID ROLLER ELEMENTS HAVING A FIRST POSITION OUT OF DRIVING COOPERATIVE ENGAGEMENT WITH SAID RADIALLY SPACED SURFACES AND A SECOND POSITION IN DRIVING COOPERATIVE ENGAGEMENT WITH SAID RADIALLY SPACED SURFACES, YIELDABLE MEANS FOR HOLDING SAID ROLLER CAGE IN A FIRST POSITION WHEREIN SAID ROLLER ELEMENTS ARE IN THEIR SAID FIRST POSITION, AND MEANS FOR EFFECTING MOVEMENT OF SAID ROLLER CAGE TO A SECOND POSITION WHEREIN SAID ROLLER ELEMENTS ARE IN THEIR SAID SECOND POSITION IN RESPONSE TO A PREDETERMINED AMOUNT OF RELATIVE ROTATION BETWEEN SAID PLANET CARRIER AND SAID ONE OF SAID SIDE GEARS OVERCOMING SAID YIELDABLE MEANS, SAID MEANS FOR EFFECTING MOVEMENT OF SAID ROLLER CAGE IN RESPONSE TO A PREDETERMINED AMOUNT OF RELATIVE ROTATION BETWEEN THE PLANET CARRIER AND THE SIDE GEAR COMPRISING VISCOUS SHEAR COUPLING MEANS INCLUDING A PORTION OF SAID ROLLER CAGE EXTENDING INTO A SLOT FORMED IN SAID PLANET CARRIER AND THE WALLS OF WHICH HAVE ON OPPOSED SPACE COOPERATIVE RELATIONSHIP WITH THE SURFACES OF THE PORTION OF SAID ROLLER CARRIER EXTENDING THEREINTO.