Patent ID: 10396629

Abstract:
An electric motor comprising a gearbox housing containing a gearbox, a sump, a first-stage shaft rotatably mounted in the gearbox housing, and a rotatably-mounted motor shaft coupled to the first-stage shaft of the gearbox. The first-stage shaft has an internal passageway defined along the longitudinal axis of the first-stage shaft and extending between opposite first and second ends thereof. At the second end the internal passageway communicates with the sump. The rotatably-mounted motor shaft is coupled to the first end of the first-stage shaft. The motor shaft has an internal passageway defined along the longitudinal axis of the motor shaft and extending between opposite first and second ends thereof. At the second end thereof, the internal passageway of the motor shaft communicates with the internal passageway of the first-stage shaft at the first end thereof. The internal passageways of the motor shaft and first-stage gearbox shaft define a coolant path for liquid coolant, the coolant path beginning at the first end of the motor shaft and proceeding entirely through the internal passageways of the motor shaft and the first-stage shaft, and the coolant path terminating at the sump, where coolant exiting the internal passageway of the first-stage shaft at the second end thereof collects.