Patent ID: 8026643

Claim:
An electrical machine, comprising: a housing; a laminated stator core received in the housing and having opposite end windings; a rotor; an internal cooling circuit comprising rotor cooling channels extending axially through the rotor and arranged on two concentric circles for circulation of a gaseous coolant; fan blades provided on a first rotor end face of the rotor and located entirely radially outside of an outer one of the two concentric circles of the rotor cooling channels; a first air guide cylinder arranged between the two concentric circles interacting with the fan blades to guide the coolant from one of the rotor cooling channels on one of the two concentric circles across one of the end windings to the other one of the rotor cooling channels on the other one of the two concentric circles, said first air guide cylinder extending axially from the first rotor end face and terminating in an outwardly pointing part positioned axially outside of the fan blades, wherein the outwardly pointing part of the first air guide cylinder extends radially at least to a radially outer circumferential edge of the fan blades; and a second air guide cylinder arranged on a second rotor end face of the rotor for guiding the coolant, wherein the first and second air guide cylinders are identical in shape and size.