Rotor end ring arrangement for dynamoelectric machines

Claim 1

IN AN ELECTRIC MOTOR HAVING A STATOR AND A FRAME ASSEMBLY, A SHAFT, A ROTOR MOUNTED ON SAID SHAFT AND COMPRISED OF A PLURALITY OF LAMINATIONS, SAID ROTOR BEING FORMED WITH A PLURALITY OF COOLING DUCTS EXTENDING AXIALLY THROUGH SAID ROTOR AND HAVING APERTURES AT THE ENDS THEREOF, SAID ROTOR INCLUDING A PLURALITY OF SLOTS FOR ACCOMMODATING ROTOR CONDUCTORS, A PLURALITY OF CONDUCTORS POSITIONED IN SAID SLOTS, MEANS FOR ROTATABLY SUPPORTING SAID SHAFT, AND A PAIR OF END RINGS DISPOSED AT THE RESPECTIVE ENDS OF SAID ROTOR AND JOINING SAID CONDUCTORS, AT LEAST ONE OF SAID END RINGS HAVING A PLURALITY OF SCALLOPED PORTIONS DISPOSED IN A PARTIALLY CIRCUMSCRIBING RELATIONSHIP WITH THE APERTURES OF SAID COOLING DUCTS, SAID SCALLOPED PORTIONS DIVIDING SAID END RING INTO SEGMENTAL PORTIONS PROJECTING INWARDLY OF SAID SCALLOPED PORTIONS, SAID SEGMENTAL PORTIONS PROVIDING A HEAT SINK FOR ABSORBING HEAT FROM SAID SCALLOPED PORTIONS DURING OPERATION OF THE MOTOR.