Cooling apparatus for cooling an electrical machine with a radial heat extraction

It is specified with a about a rotation axis rotor rotatably mounted a cooling device for cooling an electrical machine, which is disposed on a central rotor shaft. The cooling device comprises at least one disposed on the rotatable rotor shaft thermal coupling element for transporting heat from a radially inner region to a radially outer region. The thermal coupling element dips at least in a partial region of its circumference in a stationary reservoir having a condensed first cooling agents. Furthermore, an electrical machine with a rotatably mounted about a rotation axis rotor, which is disposed on a central rotor shaft, and such a cooling device is provided.