An electric machine includes a housing, a rotor including a rotor shaft and a rotor laminated core, and a stator including a stator laminated core with grooves in which stator windings are received, through which a coolant can flow, and wherein a respective tooth of the stator laminated core is arranged between two respective grooves arranged adjacent to one another in a circumferential direction. An annular gap is included between the rotor and stator laminated cores and a tooth head ring arranged in the annular gap, a respective recess of the tooth head ring arranged between two tooth heads of the tooth head ring arranged adjacent to one another in a circumferential direction of the tooth head ring. A wall element is arranged in the annular gap and seals the stator against the rotor such that, from the stator via the annular gap, no coolant moves towards the rotor.

A rotary electrical machine in which a rotor and a stator are housed in a housing and a coil of the stator is cooled using gas. The stator includes an annular coil end protruding from an end portion of the stator in an axial direction thereof. The housing includes an introduction port configured to allow gas for cooling the rotary electrical machine to be introduced from an outside of the housing toward the coil end. The coil end includes a flow path configured to allow the gas introduced from the introduction port to pass from an outer peripheral side to an inner peripheral side. A cooling air control member configured to guide the gas introduced from the introduction port to the flow path of the coil end is provided between the coil end and the housing in the axial direction.

Presented are electric machines with rotor shaft-mounted heat pipes/vapor chambers thermally coupled to endcap-integrated heat sinks, methods for making/using such machines, and vehicles equipped with such machines. An electric machine includes an outer housing, a stator assembly mounted to the housing, and a rotor assembly rotatably mounted adjacent the stator assembly. The stator assembly includes one or more stator windings mounted to an annular stator core. The rotor assembly includes one or more electromagnetic rotor windings mounted to a cylindrical rotor core. A rotor power transfer circuit (PTC) is electrically connected to the rotor assembly to electrify the rotor winding(s). A rotor shaft is attached to the rotor core to rotate in unison therewith. One or more heat pipes are mounted on the rotor shaft's outer surface and project axially between the rotor PTC and rotor core. Each heat pipe passively extracts and transfers thermal energy from the rotor PTC.