Coreless rotating electrical machine with stator including cylindrical coil and cooling method therefor

A method for cooling a coreless rotating electrical machine, the coreless rotating electrical machine comprising:

• a stator having an energizeable coreless cylindrical coil and a lid-type mount which fixes one of end faces of the cylindrical coil, and in which a drive shaft is rotatably coupled to a first center part, and
• a rotor having a cup-type mount opposingly positioned with respect to the lid-type mount, having a bottom, an inner cylindrical air-channel forming body and an outer cylindrical air-channel forming body, and in which the drive shaft rotatably coupled to the lid-type mount is coupled and fixed to a second center part, and a plurality of magnets equipped on an inner surface of the outer cylindrical air-channel forming body or an outer surface of the inner cylindrical air-channel forming body with intervals with respect to each other in a circumference direction of the cylindrical coil,
• wherein the cup-type mount has a first air space which forms an air gap formed by the bottom, the inner cylindrical air-channel forming body and the outer cylindrical air-channel forming body, the cylindrical coil is arranged in the air gap as suspended such that another end face of the cylindrical coil leaves a clearance between the bottom, with a plurality of the equipped exposed magnets, a second air space positioned in an inner side of the cylindrical coil and a third air space positioned in an outer side of the cylindrical coil, between one of end faces of the cup-type mount and the lid-type mount, and the cup-type mount has vent holes on the bottom for taking ambient air into the second air space,
• wherein the method comprising steps of:
• operating the rotor by energizing the cylindrical coil;
• taking the ambient air into the second air space via the vent holes under differential pressure generated around the rotor by rotation thereof and rotation of a plurality of the magnets;
• directly cooling a plurality of the heated magnets exposed in the first air space and the cylindrical coil arranged in the first air space by the ambient air taken into the second air space which flows through the first air space under differential pressure generated around the rotor by rotation thereof and rotation of a plurality of the magnets;
• and
• discharging the ambient air which flowed through the first air space under differential pressure generated around the rotor by rotation thereof and rotation of a plurality of the magnets via the third air space from the coreless rotating electrical machine.