Patent ID: 7667358

Claim:
A cooling structure of a superconducting motor having a superconducting coil attached to a rotor, the cooling structure comprising: a rotating shaft penetrating through and fixed to the rotor; and a refrigerant circulation tube through which a refrigerant for cooling the superconducting coil circulates, wherein a groove is formed on an outer surface of the rotating shaft, and the refrigerant circulation tube is disposed inside the groove, wherein the refrigerant circulation tube includes: a first pipe having a first outgoing path section and a first returning path section that are coupled to a supply source of the refrigerant for cooling the superconducting coil; a second pipe having a second outgoing path section communicated with the first outgoing path section of the first pipe and a second returning path section communicated with the first returning path section of the first pipe, wherein the second pipe is fixed to an axial end of the rotating shaft and is rotatably coupled to the first pipe; and a refrigerant circulation pipe having a third outgoing path section communicated with the second outgoing path section of the second pipe and a third returning path section communicated with the second returning path section of the second pipe.