ROTARY ELECTRIC MACHINE

PURPOSE:To facilitate design of cooling fins by a construction wherein radiating fins fixed on the stationary side are joined through lubricating oil to the radiating part of a heat transfer device arranged within a rotary shaft projecting into the interior of an end cover. CONSTITUTION:A heat pipe 11 is provided in a rotary shaft of a rotor, and the radiating part of this pipe is arranged within a rotary shaft 1 projecting into the interior of an end cover which is mounted on one side of an enclosed frame. Heat emitted from the radiating part is radiated by a cooling fan 9 provided separately. Radiating fins 7 in the arbitrary number are provided in the interior of the end cover, and inner peripheral ends of the radiating fins 7 are fixed to a cylindrical case 13 provided with a spacing relative to the surface of the rotary shaft. The cylindrical case 13 is in turn fixed to the enclosed frame or a bearing 12, and lubricating oil is poured into a space 16 defined between the rotary shaft and the cylindrical case. By so doing, since the radiating fins are joined with the rotary shaft through the lubricating oil, it becomes possible to provide the radiating fins on the stationary side and hence to design those fins without the need of taking into account the centrifugal force.