A method for dissipating heat in a housing defining an internal chamber for at least partially receiving motor inner workings and communicating with an air inlet and an air outlet each being formed in the housing , the method comprising: drawing, by a pump structure , the air into the internal chamber via the air inlet ; expelling, by the pump structure , the air from the internal chamber via the air outlet , wherein the housing includes a duct having a first opening communicating with the air inlet and a second opening within the internal chamber , wherein the pump structure comprises a centrifugal fan exposed to the second opening of the duct , wherein the centrifugal fan comprises a plurality of blades rotatable with a rotor of the motor inner workings , each blade of the plurality of blades comprises a planar structure with a wide portion and two narrow portions radially separated by the wide portion , wherein an axis of rotation of the rotor is defined by a central motor shaft , wherein the housing comprises a first cover , a second cover and a sidewall ; wherein the second cover is connected to the duct ; wherein the sidewall extends in axial direction and encircles the internal chamber forming the side surface of the internal chamber that is perpendicular to the first cover and the second cover ; wherein the rotor is surrounding a stator ; wherein the rotor is installed on the sidewall ; wherein the stator surrounds the duct or is located within the duct ; wherein each blade of the plurality of blades of the centrifugal fan is fixed to the first cover ; wherein each blade of the plurality of blades has a shaft-ward edge of the wide portion , the shaft-ward edge being an edge of the wide portion facing the central motor shaft , wherein the shaft-ward edge nearly touches, but does not touch an outer surface of the duct , and wherein a cylindrical volume of space encircled by the shaft-ward edges of the blades functions as an extension of the duct . drawing, by a pump structure , the air into the internal chamber via the air inlet ; expelling, by the pump structure , the air from the internal chamber via the air outlet , wherein the housing includes a duct having a first opening communicating with the air inlet and a second opening within the internal chamber , wherein the pump structure comprises a centrifugal fan exposed to the second opening of the duct , wherein the centrifugal fan comprises a plurality of blades rotatable with a rotor of the motor inner workings , each blade of the plurality of blades comprises a planar structure with a wide portion and two narrow portions radially separated by the wide portion , wherein an axis of rotation of the rotor is defined by a central motor shaft , wherein the housing comprises a first cover , a second cover and a sidewall ; wherein the second cover is connected to the duct ; wherein the sidewall extends in axial direction and encircles the internal chamber forming the side surface of the internal chamber that is perpendicular to the first cover and the second cover ; wherein the rotor is surrounding a stator ; wherein the rotor is installed on the sidewall ; wherein the stator surrounds the duct or is located within the duct ; wherein each blade of the plurality of blades of the centrifugal fan is fixed to the first cover ; wherein each blade of the plurality of blades has a shaft-ward edge of the wide portion , the shaft-ward edge being an edge of the wide portion facing the central motor shaft , wherein the shaft-ward edge nearly touches, but does not touch an outer surface of the duct , and wherein a cylindrical volume of space encircled by the shaft-ward edges of the blades functions as an extension of the duct . <EOS>