GB319479A - Improvements in or relating to the cooling of dynamo-electric machines - Google Patents

Abstract

319,479. Siemens -Schuckertwerke Akt.-Ges., and Dieterlen, M. Sept. 10, 1928. Dynamos and motors, cooling and ventilating.- In a cooling arrangement for open-type machines having an open-circuit cooling air path, the air is admitted freely to the spaces between the rotor coil ends and the rotor shaft at both ends of the machine while the spaces between the coil ends and the stator edge are covered so as to form enclosed chambers, and at least one fan is mounted on the shaft with its suction side communicating with the enclosed chambers to lower the pressure therein. In the form shown in Fig. 1, the fans are mounted on the enclosing discs 11, 12 which are mounted on the bindings of the projecting ends of the rotor windings and extend outwards to the edges 13 of the stator. The fans draw air through ducts 5 and 7 in the commutator and rotor hubs and through the ventilating ducts 8 in the rotor iron, this air being directly expelled without passing over the stator structure. Air is also drawn in through central openings 16 in the stator and is expelled with that from the rotor. Fig. 2 shows a double-commutator machine in which the fan wheels 11, 12 are mounted on the commutators with intervening insulation 18 with their blades 19 at substantially the same radius as the machine air-gap so that the warm air current from one member of the machine cannot reach the other member. The spaces between the outer edges of the fan wheels and the edges of the stator are closed by shields 22 with guide walls 21 for directing the emerging air as shown by the arrows.